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[May 14, 1970 Another Perfect Emergency (Saving Apollo-13)

May 14, 2025 Kaye Dee Leave a comment

[New to the Journey? Read this for a brief introduction!]

by Kaye Dee

On 5 May, the Apollo-13 crew visited the Grumman Aircraft Engineering Corporation factory in Bethpage, New York, to thank the company for its lifesaving Lunar Module, without which the recent lunar mission would have ended in disaster.

left to right: Apollo-13 astronauts Haise, Swigert, and Lovell during their visit to Grumman's Bethpage plant

The Grumman team’s contribution to the successful outcome of the mission – understanding the full capabilities of the vehicle they had designed so that it could be pressed into service as the astronauts’ lifeboat – is just one example of the innovativeness and dedication of the many NASA support teams working behind the scenes in the Apollo programme.

Today, I want to tell another behind-the-scenes story, one that comes “straight from the horse’s mouth”, as I’ve interviewed many of the personnel involved – the crucial role played by NASA’s space tracking networks, in particular the Manned Space Flight Network (MSFN) in Australia, in saving Apollo-13. I hope it will give you some insight into the complex technical and logistical operations that were required to respond to the emergency, and a feel for the urgency with which everyone was operating.

Practice Makes Perfect

When the team at the NASA Honeysuckle Creek MSFN station outside Canberra (which is operated by Australian contractor staff, not NASA personnel from the US) were participating in extensive pre-mission simulations about two weeks before the launch of Apollo 13, their training scripts included practicing to cope with any emergency that might arise -or at least any emergency that mission planners thought might feasibly arise, however remote the possibility. According to one Flight Controller on duty during Apollo-13, the complete failure of all the Command Module power systems was “so far down the line, if anyone had asked us to simulate it ahead of time we would all have said he was being unrealistic.”

In the above article for the Canberra Times, just three days before launch, Station Director Mr. Don Gray was quoted as saying “I have never seen anything as bad as we make it in these tests actually happen yet.” Little did he know then that this would turn out to be the most ironic statement of the year, as the MSFN – and Honeysuckle Creek in particular – was about to face a situation even more challenging than any simulation!

A view of HSK at night, taken just a few days ago

Keeping Track

I’ve written about NASA’s space tracking networks in some previous manned spaceflight articles, so for those new to the Journey, let me encourage you to read my pieces on Apollo-8 and 11 for more background on these vital segments of NASA’s space support infrastructure.

Three MSFN stations were specifically established to support Apollo lunar missions: Goldstone in California, Honeysuckle Creek, and Fresnedillas, near Madrid, Spain. Each of these stations has been sited close to a Deep Space Network (DSN) station, which support NASA’s unmanned lunar and planetary exploration probes. Since the two types of station share the same technology, the DSN station can back-up the MSFN in the event of failure during a lunar mission.

When the Command Module and Lunar Module are operating independently during the lunar phase of an Apollo mission, the paired DSN and MSFN stations can support one spacecraft each, ensuring more efficient communication with Mission Control for both vehicles.

Additional support during launch, Trans Lunar Injection and re-entry, when the Apollo spacecraft might be out of contact with ground stations, is provided by three tracking ships and a fleet of eight Apollo Range Instrumented Aircraft (ARIA), stationed in the United States and Australia.

NASA tracking ship USNS Vanguard is often based in Sydney during Apollo missions

Something’s Wrong!

Almost before Apollo-13 Command Module Pilot Jack Swigert could tell Mission Control "Houston, we've had a problem”, operations personnel at the Goldstone (callsign GDN) and Honeysuckle Creek (callsign HSK) stations knew there was something wrong. At the time, both stations could “see” the spacecraft, but at 13:08 Australian Eastern Standard Time (another 13 in this mission’s supposed catalogue of unlucky numbers!) they suddenly lost their lock on the Command Module’s signal.

As the receiver operators tried to re-acquire communication, they were only able to find a weak signal coming from the spacecraft, which had switched from its main S-Band high-gain antenna to the smaller omni antennae. This was probably due to the panel blown out of the side of the Service Module hitting the big antenna on its way past.

View of the damage to Apollo-13's Service Module showing where the panel blew out. The probably-damaged main S-Band antenna is to the lower left of the damaged section

This weaker signal combined with the erratic behaviour of the spacecraft following the explosion caused the receiver operators at GDS, HSK, and Madrid (MAD) in its turn, difficulty in holding onto the weak, fluctuating signal with their 85ft antennae for the rest of the mission.

Australia Pitches in to Help

Listening to the tense conversations between the Odyssey and Mission Control at Honeysuckle Creek, they first thought there was a communications problem with the spacecraft, but the seriousness of the crisis was brought home to them when Houston called the Operations Supervisor at HSK to ask, “How long would it take to get Parkes up?”

The Parkes Radio Telescope (NASA callsign PKS), is Australia’s world-leading 210ft radio astronomy instrument, which NASA “hires” on occasion to support planetary probes and Apollo missions: the majority of the lunar surface television from the Apollo-11 mission was brought to the world via the Parkes telescope. It was not scheduled to receive Apollo-13’s lunar television, because the astronauts would have been using a big portable umbrella antenna for communications from the lunar surface.

The Parkes Radio Telescope stands in open paddocks about 20 miles from the town that gives it its name. This view was taken around the time of Apollo-12

It was at this point that Station Director Gray realised how serious Apollo-13’s situation really was: “You don’t just casually ask to use the antenna at Parkes without making high level arrangements with plenty of warning.” Mission Control needed good telemetry from the Command and Service Modules to diagnose the spacecraft issues – and with Apollo-13 soon to pass out of range of the 210ft dish at the Goldstone DSN station, Parkes, with its much greater sensitivity than the MSFN's 85ft antennae, offered the best opportunity to capture the fluctuating telemetry and communications signals from the Lunar Module when Apollo-13’s Command Module was powered down to conserve its batteries for use during re-entry.

With carte blanche from NASA to do and spend whatever was necessary to get the radio telescope operational in its PKS mode as soon as possible, Australia swung into action!

In Record Time

To get PKS operational, technicians from Honeysuckle Creek’s DSN twin station, Tidbinbilla (TID), together with the technical staff at the radio telescope (operated by the Commonwealth Scientific and Industrial Research Organisation, or CSIRO) accomplished in just ten hours, what it would normally take them a week to complete!

Apollo-12 communication and telemetry equipment installed at the Parkes Radio Telescope, available for use during the Apollo-13 emergency

While a crew from TID flew the 200 miles to Parkes in a hastily-arranged Cessna, arrangements were made with the Director of the Parkes telescope, Dr. John Bolton, to convert it from radio astronomy to NASA use. The Indian researcher using the telescope at the time agreed to delay his project, and the engineers supporting him removed his equipment while Parkes staff began to install NASA equipment that was still onsite from Apollo-12. To configure the equipment, NASA hastily flew out one of its experienced communication engineers from the Goddard Space Flight Centre, which manages tracking and communications for the Apollo programme. CSIRO also made arrangements to send additional supplies and personnel from Sydney by plane. Everyone worked 16-hour days until Apollo-13 was safely back on Earth.Catching some rest at the end of a 16-hour shift at Parkes

Making Connections

To enable PKS to send the signals it received back to the United States, temporary connections had to be made between the facility, NASA’s communications control centre in Sydney and the satellite communications ground station located in Moree in north-western New South Wales.
Cover of a brochure showing the Overseas Telecommunications Commission's INTELSAT ground station at Moree, used to send NASA data via satellite to the United States

Domestic communications in Australia are managed by the PMG (Post Master General’s Department). They, too, immediately swung into action, sending technicians out in the dead of night to re-connect the temporary microwave links between Parkes and Sydney. “We dropped everything we were doing with the state networks and concentrated on the Apollo circuits,” as they expected that PKS, HSK and TID would play a crucial role after the spacecraft’s trans-Earth injection.

Teams from the PMG, the Australian Broadcasting Commission and private contractors, installed temporary microwave circuits from Parkes and Canberra, which involved the erection of six aerials up to 60 feet high in the middle of the night. The microwave links were installed across hundreds of miles in around 12 hours!

NASA also wanted a high-capacity data link between the MSFN tracking station in Carnarvon (CRO), in remote northern Western Australia and its INTELSAT ground station two and a half miles away. At just 30ft, CRO might have had a much smaller antenna than HSK, TID and PKS, but NASA wanted everything they could get.

Two outside broadcast vans were despatched from Perth to make the almost 600-mile trip to Carnarvon to connect the two stations there. “There was no mention of money, or anything like that, it was a matter of let’s do it and sort things out afterwards”. Rescuing Apollo-13 was more important than budget or bureaucracy! The 30ft Apollo tracking antenna at Carnarvon MSFN station. Primarily used for tracking Apollo missions in Earth orbit, it could detect signals out to near-lunar distances

Untangling Signals

In my Apollo-13 article, I noted how communications difficulties arose between the Lunar Module (LM) Aquarius and Mission Control because it was using the same frequency as the mission’s spent S-IVB stage, which was following Apollo-13 to the Moon.

The mission plan was for Apollo-13’s S-IVB rocket to crash on the Moon, so that the impact could be detected by the Passive Seismic Experiment left by Apollo-12. Extra batteries had been added to the rocket stage so that it was communicating until impact. Had the mission gone to plan, the S-IVB would have impacted with the Moon well before the LM was fired up.

The Apollo-12 Passive Seismic Experiment which detected the impact of Apollo-13's S-IVB stage on the lunar surface

With both the S-IVB and LM transmitters on the same frequency, it was like having two radio stations on the same spot on the dial of your radio. Which signal does the receiver try to lock onto?

At Goldstone, with Apollo-13 still in view when the emergency began, the 210ft dish, with its narrower beam-width, managed to discriminate between the two signals and the telemetry and voice links were restored. But in Australia, until PKS was operational Honeysuckle Creek would be tracking with its smaller 85ft antenna. Its ten receivers could randomly lock onto one signal or the other – and that is what happened!

HSK used a technique employed in the Deep Space Network to lock onto faint signals from interplanetary probes amidst the “background noise” of the galaxy to “pull” the frequencies apart by tuning the station transmitters appropriately.

An incorrect decision by Mission Control to tune the frequency of one transmitter in a particular way then brought all the frequencies back together again! The presence of two uplink carrier signals caused interference that the crew was hearing.

Tense moments at Honeysuckle Creek while the tangled signals from Apollo-13 and its S-IVB stage are unravelled

Fortunately, an emergency procedure previously developed and practised at HSK ultimately resolved this issue. “The only way out of this mess was to ask the astronauts in the LM to turn off its signal so we could lock on to the S-IVB, then turn the LM back on and pull [its signal] away from the Saturn signal. When we could see the Saturn-IV downlink go way out to the prescribed frequency, we put the second uplink on, acquired the LM, put the sidebands on, locked up and tuned away from the S-IVB. Then everything worked fine.”

The Final Leg

With the big dishes at Goldstone and Parkes both operational, and support from the smaller antennae in the US, Australia and Spain, the reliable communications established between Mission Control and the Apollo-13 astronauts made possible by the Manned Space Flight Network and its DSN twins was a crucial factor in saving the mission that has been dubbed a “successful failure”.

Elements of the MSFN supported Apollo-13 all the way to splashdown. CRO used its powerful FPQ6 radar to observe the separation of the Command Service Modules, as well as Odyssey and Aquarius. It also tracked the Odyssey as it made its unusual "foldback" track over the Indian Ocean.

Chart showing Apollo-13's re-entry ground track. It gives a good idea of the ‘foldback’ or reversal of Apollo 13’s ground track as its increased speed towards re-entry reversed its direction with respect to the Earth. The Australian MSFN stations are also marked.

Honeysuckle Creek was the last ground station to track the re-entry phase of the mission when Apollo-13 re-entered the Earth’s atmosphere and crossed eastwards across Australia, but three ARIA aircraft, flying out of Australia were on station. They were waiting to make contact after the re-entry blackout and see Apollo-13 to the completion of its odyssey: ARIA 2 was about 300 nautical miles up-track from the predicted splashdown point, ARIA 4 was near the predicted point, and ARIA 3 was about 300 nautical miles down-track, in case the Command Module Apollo-13 overshot the landing target.

ARIA 4 tracking aircraft on the ground at Perth Airport, Western Australia, before taking up station to support Apollo-13's safe splashdown

Well-Deserved Recognition

Too often, the dedicated “we’ll do what it takes” effort behind-the-scenes of a major event goes un-noticed, so it is worth noting that the work of the MSFN and DSN facilities in Australia, along with that of Parkes and the CSIRO, PMG and supporting contractors was recognised with commendation in the Australian Parliament and from the Goddard Space Flight Centre Network Director. President Nixon himself sent the message below to Australian Prime Minister Mr. John Gorton.

Without the efforts of hundreds of NASA, contractor and local communications network personnel across the world to maintain contact with the stricken spacecraft, enabling vital communication between the astronauts and Mission Control, the outcome of the Apollo-13 emergency might have been very different. Thanks to training, professional competence and determination, it has become instead an outstanding example of "the perfect emergency".

[New to the Journey? Read this for a brief introduction!]

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Science / Space Race

[April 22, 1970] “Houston, We’ve had a Problem Here!” (Apollo-13 emergency in space)

April 22, 2025 Kaye Dee 2 Comments

[New to the Journey? Read this for a brief introduction!]

by Kaye Dee

We all breathed a sigh of relief when the astronauts of Apollo-13 returned to Earth safely a few days ago, after the Apollo programmes’ first (and hopefully last) inflight emergency, but superstitious people are claiming that Apollo-13 was unlucky because of a prevalence of “13s”! After all, the mission was launched at 13:13 Houston time (but somewhere in the world there will always be a place where the time is 13: something!) and the explosion that caused its inflight emergency occurred on 13 April (but only in certain timezones – it was already 14 April in Australia and most of the world east of the United States).

Don’t tell me the Apollo-13 crew were “unlucky”; in fact, they were immensely lucky that when something did go wrong they were a team with the right skills for the situation. As seasoned test pilots, the crew were experienced at working in critical situations with their lives on the line, and their professional skills as astronauts were matched by the “tough and competent” (to quote Flight Director Mr. Gene Kranz) Mission Control teams, backed by highly trained engineers and scientists – all determined to “return them safely to the Earth”, just as President Kennedy committed NASA to do when he set the goal of a manned lunar landing by 1970!

Timeline of major mission events during Apollo-13

Crew Switcheroo
The prime crew for Apollo-13 changed multiple times, the last alteration occurring just days before launch! Instead of rotating the Apollo-10 back-up crew to become the prime crew for Apollo-13 – the normal procedure – Director of Flight Crew Operations, Mr. Deke Slayton, designated astronauts Alan Shepard (Commander), Stuart Roosa (Command Module Pilot) and Edgar Mitchell (Lunar Module Pilot) as the Apollo-13 prime crew. However, although he was the first American in space, Captain Shepard had only recently returned to flight status after a lengthy medical issue. It was felt that he needed more training time, so in August 1969, his crew was swapped with the prime crew for Apollo-14.

The prime crew for Apollo 13 then became US Navy Captain James Lovell, as Commander, civilian Mr. Fred Haise as Lunar Module Pilot (LMP) and USAF Lt. Col. Ken Mattingly as Command Module Pilot (CMP).

Official crew portrait for Apollo-13. L.-R. Jim Lovell, Ken Mattingly and Fred Haise. They are shown with ancient scientific and navigation instruments hinting at the classical elements in the mission patch and callsigns

Unfortunately, just a week before launch back-up LMP Charles Duke contracted German measles (rubella) from a child and accidentally exposed both the prime and back-up crews to the disease. CMP Mattingly was found to have no immunity, and the astronauts’ medical team had serious concerns that he could become too sick to perform adequately during the flight if he began to experience symptoms of the disease.

Normally, NASA policy would dictate that the back-up crew step into the mission. However, since back-up LMP Duke also had the measles, this wasn’t feasible. Just three days before launch, the difficult decision was made to replace Lt. Col. Mattingly with Mr. Jack Swigert, the fortunately-immune back-up CMP. This made the final crew for Apollo-13 Lovell, Haise and Swigert. Astronaut Mattingly will be re-assigned to a later Apollo mission, probably Apollo 16.

The last minute Apollo-13 crew portrait, following the swap of Ken Mattingly to Jack Swigert

Who’s Who?
Although he announced his intention to retire from NASA prior to Apollo-13, 42-year-old Mission Commander James “Jim” Lovell is the world's most experienced astronaut, the record holder for the most time in space, with 572 hours aboard Gemini-7, Gemini-12 and Apollo-8!

Members of the fifth astronaut group, selected in 1966, Captain Lovell’s crewmates may have both been space rookies, but fortuitously they each had specialisations that provided vital knowledge and experience during the in-flight emergency.

Mr. Fred Haise, the Lunar Module pilot (LMP), is a 36-year-old aeronautical engineer, who was both a Marine Corps and Air National Guard fighter pilot. A civilian research pilot for NASA before his selection as an astronaut, Mr. Haise previously served as back-up LMP for Apollo-8 and 11. He is a specialist on the Lunar Module (LM), having spent fourteen months at the Grumman factory where the spacecraft are built.

Mr. John “Jack” Swigert, the Command Module Pilot (CMP), is 38 years old, with degrees in mechanical engineering and aerospace science. He has served in the US Air Force and in state Air National Guards and was an engineering test pilot immediately prior to his astronaut selection. A specialist in malfunctions of the Command and Lunar Modules, Mr. Swigert “practically wrote the book on spacecraft malfunctions.”

Knowledge from the Moon
It’s probably fortunate that, like Apollo-11, Captain Lovell’s original crew made the decision that the Apollo-13 mission patch would not carry their names: when the last minute crew swap occurred, no changes were required to the design. Instead of names, the Apollo-13 patch carries the motto “Ex Luna, Scientia”, Latin for “From the Moon, knowledge”. This references Apollo-13’s intended role as the second ‘H’-class mission, designed to demonstrate precision landing capability so that the crew could explore a specific site on the Moon. As a Navy officer, Captain Lovell derived the motto from that of the US Naval Academy, “Ex scientia, tridens ("From knowledge, sea power").

A powerful image of the Sun rising behind the horses of the god Apollo’s chariot forms the centrepiece of the design. As Apollo is the god of both the Sun and knowledge, this plays upon both the project name and the mission motto. Against the black background of space, the golden horses of Apollo prance over the Moon, their journey from the Earth (in the background) to the Moon depicted by a bright blue path. Artist Lumen Martin Winter, designer of the Apollo-13 mission patch, based the horses on a mural he previously painted for the St. Regis Hotel in New York City (below). Using Roman numerals for the mission number also complements the classical connections of the spacecraft names and callsigns.

Classical Callsigns
Captain Lovell drew upon classical mythology in selecting the Command Module callsign “Odyssey” – taken from Homer’s epic Greek poem. Since an “odyssey is “a long voyage with many changes of fortune”, it turned out to be an extremely appropriate choice indeed! The name was also a nod to the classic science fiction film "2001: a Space Odyssey".

For the Lunar Module, the crew selected the callsign “Aquarius”. Although the media have linked the callsign to the song in the musical “Hair”, it is actually meant to reference Aquarius, the cup-bearer of the Graeco-Roman gods, and bringer of water – the only water on the Moon being that carried there by the Apollo crew.

Medieval illustration of Aquarius watering the Earth

Preflight Preparations
Apollo-13’s launcher, AS-508, had some slight modifications compared to earlier Saturn-V vehicles, to prepare for the future J-class missions which will carry heavier payloads. New “spray-on insulation” was used for the liquid hydrogen propellent tanks in the S-II second stage. The rocket also carried additional fuel, as a test for future launches, making it the heaviest Saturn-V yet flown.

The intensive preparation for the Apollo-13 crew included over 1,000 hours of mission-specific training, with a much greater focus on geology, since the intended landing area in the hilly Fra Mauro formation (named for a 15th Century cartographer monk) is of significant geological interest. If rocks from this area could be dated, they might improve our understanding of the early geological history of both the Moon and the Earth. Scientist-astronaut Harrison Schmitt, himself a geologist, was heavily involved in the crew’s geological training.

Jim Lovell and Fred Haise during geology training in Hawaii

Due to the difficulty of distinguishing astronauts Armstrong and Aldrin from each other in Apollo-11 photographs, NASA introducec a means of differentiating crew members from each other on the Moon by adding red stripes on the helmet, arms and legs of the commander's spacesuit. This system will now be implemented on Apollo-14.

Experiments That Might Have Been
A major component of Apollo-13’s lunar surface activities would have been the installation of a new Apollo Lunar Surface Experiment Package (ALSEP), powered by a SNAP-27 radioisotope thermoelectric generator (RTG). This small nuclear generator contains 8.36lb of plutonium oxide. The fuel capsule is intended to withstand the heat of re-entry into the Earth's atmosphere in the event of an aborted mission, which means that Apollo-13’s RTG may have survived Aquarius’ re-entry on return to Earth, splashing down into a remote area of the southern Pacific Ocean.

Mission Commander Lovell practicing the deployment of an ALSEP instrument during training

Like Apollo-11 and 12, Apollo-13’s ALSEP included a seismometer (the Passive Seismic Experiment), which was to be calibrated by the impact of Aquarius’ ascent stage, a Lunar Atmosphere Detector (LAD) and a Dust Detector. New to the Apollo-13 instrument package was a Heat Flow Experiment (HFE), and a Charged Particle Lunar Environment Experiment (CPLEE), designed to measure solar protons and electrons reaching the Moon.

A Shakey Start
Originally scheduled for launch in March, Apollo-13 was delayed for a month while NASA re-considers how it will schedule the remaining Apollo missions out to Apollo-19, now that Apollo-20 has been axed due to President Nixon’s budget cuts.

The mission hit trouble right at the start: five and a half minutes after liftoff on Saturday 11 April (US time). The crew felt “a little vibration”, then the centre engine of the S-II stage shut down two minutes early. This required the remaining four engines to burn and additional 34 seconds longer, while the S-IVB third stage had to burn 9 seconds longer to put the spacecraft into orbit. But with the extra fuel on board for this flight, the engine failure fortunately didn’t cause any major problem.

A successful trans lunar injection burn placed Apollo-13 on course for the Moon, with the CSM and LM docking occurring 20 minutes’ later. Unlike previous lunar missions, after the LM was extracted from the S-IVB stage, the stage was not sent off into solar orbit, but targetted to impact the Moon so the vibrations could be detected by the Apollo-12 seismometer. This would later cause unexpected communications complications after the accident occurred.

Apollo-13's S-IVB stage heading towards the Moon

“We’re Bored to Tears”
With the spacecraft safely on its way to the Moon, the first phase of the flight was uneventful. Approaching 31 hours into the flight, the crew performed a burn to place Apollo 13 on a hybrid trajectory, enabling Aquarius to ultimately land at the Fra Mauro site. This change from the free-return trajectory used on earlier missions would cause later complications for returning the astronauts to Earth: on a free-return trajectory, no further engine burns were necessary to ultimately bring the spacecraft home, but a hybrid trajectory would miss Earth on its return leg, unless further burns were performed.

Apollo-13 White Team Flight Director Mr. Gene Kranz catching up on his paperwork in Mission Control during the calm before the storm

The day after launch, Mr. Swigert became worried by the realisation that, in the rush to replace Ken Mattingly, he had forgotten to file his Income Tax Return, and needed to apply for an extension! Fortunately for him, an amused Mission Control advised that “American citizens out of the country get a 60-day extension on filing; assume this applies to you.”

With Apollo-13’s telemetry showing that the spacecraft was “in real good shape”, on 13 April Capcom Joe Kerwin told the crew “We are bored to tears down here.”—a situation that was soon to change.

The Last Apollo-13 Show
Astronauts Lovell and Haise entered the LM to test its systems about an hour before a major television broadcast, scheduled for 55 hours into the mission.

With Commander Lovell acting as MC, the astronauts put on a lively show, exhibiting some of their gear such as space helmets, sleeping hammocks and newly-designed bags for drinking water inside their spacesuits. From Odyssey, Captain Lovell played tinkly lounge music using a small tape recorder, and he said it was an awesome thing to see the Moon accompanied by the theme to 2001.

Mission Control during the Apollo-13 broadcast. Astronaut Fred Haise can be seen on the big screen

Disappointingly, American television viewers had become, it seems, even more bored than Mission Control with now-“routine” missions to the Moon. None of the major US networks carried the broadcasts, although they were seen in Australia and, I believe, other countries. Marilyn Lovell and Mary Haise had to go to the Mission Control VIP viewing room to see their husbands’ half hour broadcast on television.

“Houston, We’ve had a Problem Here!”
Just nine minutes after the conclusion of the television broadcast, at 205,000 miles from Earth, an incident occurred that turned Apollo-13 from a routine mission into an emergency situation: one that the media and anxious communities in the US and around the world would intently follow as soon as the news broke!

At the request of Mission Control, Mr. Swigert stirred the cryogenic hydrogen and oxygen tanks that powered the fuel cells in the Service Module (SM). This action was followed by a “pretty large bang”, felt as a jolt through the spacecraft, accompanied by fluctuations in electrical power, attitude control thrusters firing automatically and a brief loss of communications and telemetry to Earth.

Diagram of the Service Module showing the location of the fuel cells and oxygen tanks that must have been damaged by the explosion, based on the available telemtry

CMP Swigert quickly reported "Okay, Houston, we've had a problem here," confirmed moments later by the Mission Commander, "Houston, we've had a problem. We've had a Main B Bus undervolt”. This meant that the SM’s three fuel cells were not providing sufficient voltage to the second of the Service Module’s two electrical power distribution systems

Captain Lovell momentarily thought that LMP Haise had activated Aquarius’ cabin-repressurisation valve (which Haise could have done as a joke, since its bang would startle his crewmates); CMP Swigert initially thought that a meteoroid might have struck the LM, though there was no atmospheric leakage. But voltage was dropping in both electrical buses, one oxygen tank was empty, and the other leaking, and two of the three fuel cells were failing!

Headline from Australian newspaper "The Sun" just a few hours after the accident. It references Lovell's description of gas venting from the Service Module

Looking out Odyssey’s hatch window, seeking a cause for the spacecraft thrusters to be firing erratically and affecting their course to the Moon, Captain Lovell saw “gas of some sort” venting into space. Some kind of physical rupture had definitely occurred: whatever had caused the problem, the situation was serious.

Mission Control Swings into Action
Although the Flight Controllers in Houston initially assumed that their bizarre anomalous readings from Apollo-13 had to be the result of instrumentation issues, it quickly became obvious, judging from the reports from the crew, that they were dealing with a genuine emergency.

The Mission Control White Team, led by Flight Director Gene Kranz, was on duty when the incident occurred and had to deal with the initial hours afterwards. With extensive Flight Director experience going back to the Mercury programme, and including critical phases of the Apollo-11 mission, Mr. Kranz played a crucial role in the rescue of the Apollo-13 crew.

Flight Director Gene Kranz (seated) and senior Flight Controllers during the tense period following the Apollo-13 accident

With telemetry data providing some insight into the condition of the spacecraft, and support from “backroom” teams of technical specialists, White Team worked to diagnose the problems and prioritise recovery and rescue actions.

The fuel cells needed oxygen to operate, but it was rapidly leaking away. Attempting to stem the leak, they shut down the two failing fuel cells. This immediately meant the loss of the lunar landing, as mission rules prohibited going into orbit around the Moon unless all three fuel cells were functioning. With oxygen still being lost, Mr. Kranz ordered the isolation of a small oxygen supply within the Odyssey, to retain it for use with the last remaining fuel cell, which would be needed for the final hours of the mission. The CM's batteries would be needed to power the craft during re-entry, so they were also shut down to conserve power.

Lifeboat Aquarius
Ninety-three minutes after the accident, oxygen pressure in the Command Module was dropping and Mission Control determined that the last fuel cell would soon fail as oxygen ran out, leaving the CM effectively dead. Aware of training simulations that had used the LM as a “lifeboat”, Mission Control ordered the crew to transfer to Aquarius.

Lovell, Haise and Swigert had themselves already realised that Aquarius would be needed as a lifeboat, and had commenced to power-up the Lunar Module, transferring necessary information to the LM’s guidance system. They bagged up as much water as possible from Odyssey’s supply (needed for equipment cooling as well as drinking), storing the water and food supplies in Aquarius.

The Apollo-13 crew's only view of their lifeboat Aquarius in space, drifting after it was cast loose shortly before re-entry

It was going to be a tight fit for three astronauts in a spacecraft meant for two, but the crew were fortunate that the emergency occurred when they had a fully-powered and supplied Lunar Module attached to the Odyssey. Had the explosion occurred after the lunar landing, with Aquarius jettisoned, the CM would not be able to provide enough life support to keep the astronauts alive until they returned to Earth.

Apollo-13 was being surrounded by a cloud of debris from the explosion. Communications were weak and erratic, due to probable antenna damage from debris, as well as interference from the S-IVB stage also on its way to the Moon. Its tracking beacon was operating on the same frequency as the Lunar Module, as it had not been anticipated that the LM and S-IVB stage would be communicating at the same time. (I’ll cover this situation in more detail in an article in May).

Flight Controllers conferring on how best to bring Apollo-13 safely home. Note the lack of data usually present on the big screens

“Returning Them Safely to the Earth”
Apollo-13’s new mission goal became the safe return of the crew to the Earth. Vital consumables (oxygen, electricity, and water) were assessed and rationing plans devised. Calculating the best way to get the spacecraft back to Earth before supplies were exhausted became a priority, with the mindset that “failure is not an option”.

Ultimately, the safest course of action was deemed to be putting Apollo-13 back on a free-return trajectory, firing the LM’s descent engine so that the spaceship would loop around the Moon and head back to Earth. Using the large Service Module engine was ruled out, since it was uncertain if it had been damaged by the explosion.

NASA’s “Return to Earth” trajectory specialist, Miss Poppy Northcutt, calculated a new course to carry Apollo-13 around the Moon and safely home. Anxious to assist in any way they could, other astronauts arrived at Mission Control, including Lt. Col. Mattingly, who still had not developed German measles! Some would spend time in the Apollo simulators, helping to work up needed procedures, such as powering up the Command Module for re-entry with limited electricity available.

NASA Contollers and astronauts gathered in Mission Control to assist the rescue of Apollo-13. Seated, left to right, Guidance Officer Raymond F. Teague; astronaut Edgar D. Mitchell, Apollo 14 prime crew lunar module pilot; and astronaut Alan B. Shepard Jr., Apollo 14 prime crew commander. Standing, left to right, are scientist-astronaut Anthony W. England; astronaut Joe H. Engle, Apollo 14 backup crew lunar module pilot; astronaut Eugene A. Cernan, Apollo 14 backup crew commander; astronaut Ronald E. Evans, Apollo 14 backup crew command module pilot; and M.P. Frank, a flight controller

Sixty one and a half hours after launch, Aquarius’ descent engine burn put Apollo-13 back on a free return trajectory. As it looped around the Moon, Apollo-13 captured the Guinness World Record for the farthest distance from Earth attained by a crewed spacecraft – 248,655 miles.

The Moon's far side photographed by the Apollo-13 crew. The shut down CM Odyssey can also be seen in the foreground of this view from Aquarius

I’m sure you recall the tension during those 25 minutes of radio blackout when Apollo-13 was behind the Moon. People around the world tuned into television and radio, or gathered in public spaces, eager for news, now engrossed in the gripping drama being played out in space. Would the astronauts survive? Religious leaders led congregations in prayer for their safe return.

On Their Way Home
Mission Control determined that a burn following trans-Earth injection would shave 12 hours off the flight time back to Earth and land Apollo-13 in the Pacific, where the main US recovery fleet was located. Thirteen nations (another number 13!), including the USSR, offered to provide rescue ships or aircraft for emergency recovery, should the spacecraft come down off course in the Pacific, Indian or Atlantic Oceans.

When this crucial burn took place, the debris cloud surrounding the spacecraft made it impossible to use stellar navigation to check the accuracy of the firing. However, the crew were able to use the positions of the Sun and Moon to confirm that the trajectory was on target. They were going home!

The astronauts then shut down most LM systems to conserve consumables, making for a miserable return flight: in Aquarius it was extremely cold (38 °F), dark and damp, with moisture condensing out on every surface, including the windows. The same issue occurred in Odyssey, raising concerns of short-circuits occurring when it was powered back up. Fortunately, lessons learned from the Apollo-1 fire prevented that from happening.

Mission Commander Lovell tries to sleep in the extreme cold and semi-darkness of the Lunar Module

The crew slept poorly, eating and drinking little (cold frankfurters and water for dinner, anyone?). They lost weight, with Mr. Haise developing a urinary tract infection, apparently from dehydration.

Putting a Square Peg in a Round Hole
A new problem arose during the return journey – with three astronauts in the LM, dangerous levels of carbon dioxide were building up in Aquarius. They were running out of lithium hydroxide canisters, designed to scrub it from the air, and the square canisters used in Odyssey were not compatible with the round openings in Aquarius!

Jack Swigert, with assistance from Jim Lovell (just out of frame) assembles the connections for the makeshift CO2 scrubbing device nicknamed "the mailbox", which is box shaped object beside Swigert

NASA engineers fortunately found a way to fit “a square peg in a round hole,” using only items available on the spacecraft. After the instructions for building the device were radioed up, Swigert and Haise constructed it and carbon dioxide levels began dropping immediately.

The Final Leg
Apollo-13 showed a tendency to drift slowly off course, and two more mid-course correction burns were needed to keep the spacecraft within the safe re-entry flight path. Just after 138 hours into the mission, the crew jettisoned the SM from the command module, allowing the astronauts to see and photograph the explosion area for the first time. They were shocked by the extent of the damage they saw and concerned that the explosion might have damaged the heatshield.

The astronauts' only view of the Service Module, showing the extent of the damage caused by the explosion, which blew out an entire side panel.

Moving back into Odyssey, the astronauts then reactivated its life support systems, while retaining Aquarius until about 70 minutes before entry. With no heatshield of its own, the LM could not safely re-enter, but as it drifted away, watched sadly by the crew, Capcom Kerwin offered an epitaph from Mission Control: “Farewell Aquarius, and we thank you”.

There's no place like home! Earth taken from Apollo-13 in the final stages of its return from the Moon

Home at Last!
At last, on April 17 (US time),142 hours after launch, Apollo-13 re-entered Earth’s atmosphere. Its shallow re-entry path lengthened the usual four-minute radio communications blackout to six minutes, causing Mission Control to briefly fear that the CM's heat shield had failed. But Odyssey had survived and splashed down safely in the South Pacific Ocean south-east of American Samoa, just four miles from the recovery ship, USS Iwo Jima: total flight time: 5 days, 22 hours, 54 minutes and 41 seconds. Mission Control erupted in cheers!

While the world rejoiced at their safe return, the exhausted Apollo-13 crew stayed overnight on the recovery ship, without undergoing quarantine since they did not land on the Moon.

Exhausted but elated, the Apollo-13 crew are formally welcomed aboard the recovery ship, USS Iwo Jima as returning heroes after their space ordeal

The astronauts flew to Pago Pago in American Samoa the next day, then on to Hawaii, where they were re-united with their wives and President Nixon awarded them the Presidential Medal of Freedom, the highest US civilian honour. The Presidential Medal of Freedom was also awarded to the Apollo-13 Mission Operations Team, for their efforts in ensuring the safe return of the Apollo-13 crew. After staying overnight in Hawaii, Capt. Lovell, Mr. Haise and Mr. Swigert have now returned to Houston to be re-united with their families.

Returning heroes after their space ordeal. the Apollo-13 crew stand proudly with President Nixon after being awarded the Presidential Medal of Freedom

At present, the cause of the explosion that crippled Apollo-13 is unknown, so I will leave the speculation until my follow-up article in May, talking more about Apollo-13’s epic journey. I’d like to end here with the words of President Nixon, during the Presidential Medal of Freedom presentation: “You did not reach the Moon, but you reached the hearts of millions of people on Earth by what you did.”

The astronauts only learned about the extent of the pubic reaction to their emergency after they returned to Earth!

[New to the Journey? Read this for a brief introduction!]

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Fashion, music, politics, sports

[July 12, 1969] Paco Rabanne and the Theater of War

July 12, 2024 Gwyn Conaway 1 Comment

Be sure to join us today (July 13) at 9:15 AM PDT (5:15 in London) for BBC's broadcast of the first episode of Star Trek!

by Gwyn Conaway

Paco Rabanne posing with the circular chainmail that has swept Futurist fashion. The style needs no label as it's immediately recognizable as his revolutionary work.

NASA has set its sights on the moon, and their journey is mere days away.

The dead heat of summer has fallen upon us like a humid hug. We fan our sun-kissed skin and drink iced tea from sweating glassware. We crave the artificial breeze of a car ride and press damp rags into our necks. And despite our discomfort, our American breath is frozen in our lungs. Our conversations of anything else have dwindled to distracted murmurs and canceled plans.

I find myself preoccupied with broadcasts and newspapers, my mind muddied with what-ifs and what-thens. It all circles back–one revolution after another–to a single designer and how his first couture line managed to change the course of fashion from the runway to the street. How will he view the coming weeks?

Paco Rabanne.

From Rabanne's "Twelve Unwearable Dresses," 1966.

This first couture collection borrows heavily from the Byzantine period with plate mail and lamellar armor elements, giving his mail dresses an Athenian allure.

Rabanne created his first couture line only three years ago. “Manifesto: Twelve Unwearable Dresses in Contemporary Materials” showed in Paris in 1966, and forever changed the fashion landscape for women. Until that moment on his runway, industrial materials had been relegated to the theatre of war in the forms of chainmail and lamellar armor, among other notable defensive garments.

These days, though, I wonder… Is fashion not also part of the theater of war? Propaganda is considered so, which suggests public perception is a weighty tool of any nation. What better way to proclaim the perfection of one’s ideals than through beauty?

Rabanne designed this in spring of 1969. Note how it mirrors much of the shape language of the height of the Crusades from the 11th to 13th centuries, and Bedouin niqab. This speaks both to the Crusades and the recent Six-Day War in the Middle East.

An example of German hauberk chainmail in the eleventh century.

A Bedouin woman in Sinai, Egypt wearing a niqab adorned with coins sometime between 1900-1920.

Paco Rabanne seems to have reached the same conclusion as me. Though his mother was a chief seamstress for Balenciaga and followed the designer to Paris when he was five, his father was executed during the Spanish Civil War. Of course, I can’t imagine the impact of violence at such a tender age, but politics and doom are common themes of Rabanne’s public statements regarding his own reincarnation and prophecies. Both he and Salvador Dali–who run in the same circles, so I’m told–explore the idea of utter destruction in intimate artistic detail. A political endeavor in and of itself.

So it’s no surprise to me that Paco Rabanne’s construction techniques rely heavily on pliers rather than sewing needles. His unforgiving poeticism armors the modern Cold War woman as if she herself were not just a prize of war, but an active participant.

Francoise Hardy in Rabanne, 1960s. She walks with an air of severity through stately rooms flanked by officers, signaling her authority and power. The untouchable quality of Rabanne's models enhanced their otherworldly power, emulating godly women of history such as Athena, Cleopatra, and Joan of Arc.

Which brings me to one of his most recent masterpieces. Le 69, affectionately known as the Moon Bag, is constructed in the same fashion as his metal and plastic mail dresses with heavy steel. Supposedly inspired by a French butcher’s apron that dates back to the medieval period with a strap made from a toilet-flushing chain, I wonder terribly what his personal feelings are on this accessory. Given our current moment in history, I can’t help but equate it with the covetous nature of the Space Race. Who will get there first? What happens when someone wins the race?

The answer to the first question is imminent. Women will now and for many years carry the “Moon” in their hands as if we have the right to possess it.

Rabanne's "Le 69" Moon Bag.

Paco Rabanne is aware of the inherent violence of his design language. In fact, he has explicitly stated it. “My clothes are like weapons. When they are fastened they make a sound like the trigger of a revolver.” And though many critics cite his architectural background as the reason for his exceptional choices in material and technique, his motivations seem to go deeper than that.

As the Apollo 11 launch approaches, perhaps Rabanne is asking the same questions. What happens when our adversaries see the Moon in our hands?

My only hope is that the doom he feels looming in his prophecies remains there.

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Science / Space Race

[July 16, 1968] Hitching a Ride to Orbit (Orbiting Vehicle Satellite Series)

July 16, 2023 Kaye Dee 1 Comment

by Kaye Dee

The continuing hiatus in American and Soviet manned spaceflight and the present lack of unmanned lunar and interplanetary missions, has been a blessing as well as a disappointment. It's given us an opportunity to focus on some lesser-known US and USSR space programmes that are quietly going about their business largely unreported. One such is the US Air Force’s Orbiting Vehicle programme, which saw its most recent launch just a few days ago. While the Traveller has previously taken a look at some early OV1 series missions, the whole thing is worth looking at–it's really quite exciting!

Hitching a Ride on an ICBM
When the Air Force Office of Aerospace Research (OAR) was looking for a means to conduct space experiments at the lowest possible cost, it conceived the idea of using small satellites of a standardised design, launched as secondary payloads piggybacking on Atlas ICBMs being flown for missile technology development. After all, Atlas vehicles have been used to launch satellites as far back as 1958 (Project SCORE), as well as launching all the orbital missions of NASA’s Mercury programme.

This concept led to the development of Orbiting Vehicle (OV) programme, initially created in the early 1960s under the name SATAR (SATellite for Atmospheric Research). SATAR was an extension of the "Scientific Passenger Pods" (SPP) flown as external payloads on suborbital Atlas missile tests to conduct scientific experiments during their brief time in space. In its original form, SATAR was to use a larger version of the SPP, called the Atlas Retained Structure (ARS), that would carry a small satellite with its own propulsion system. When the Atlas missile reached its apogee, the satellite would be deployed from the ARS, using its propulsion system for orbital insertion.

Renamed the Orbiting Vehicle programme around 1963, this project now includes five separate series of standardised satellites, designated OV1 through OV5, each designed for a specific research goal.

OV1-3 launches in a side pod on an Atlas missile ABRES test flight

Launching OV1
The first series of OV satellites – which has seen the greatest number of launches to date – is OV1, developed by the Convair Division of General Dynamics, which also produces the Atlas vehicle. Initially, OV1 satellites were going to be launched on Atlas missiles testing nosecones for the Advanced Ballistic Re-Entry System (ABRES). However, only OV1-1 and OV1-3 ever flew piggyback on an ABRES mission, mounted in pods on the side of the missile. Both satellites were, unfortunately, unsuccessful.

View of the OV1-2 launch showing the twin top-mounted pods. Although there were two pods, only a single satellite was launched on this flight

The other OV1 missions so far have been launched on dedicated Atlas D and F boosters (retired from the ICBM programme) purchased by the OAR for the OV1 series. These flights use two modified SPP pods mounted side-by-side on top of the Atlas, enabling two satellites to be launched on each OV1 flight. The only exceptions to date have been OV1-6, which flew on the Manned Orbiting Laboratory test flight on 2 November 1966, and OV1-86, carried in a side-mounted pod on the same launch that lofted OV1-11 and OV1-12.

Small but Versatile
Using a standardised satellite design has enabled experiments to move rapidly from proposal to launch, the process taking just fifteen months on average. The operational design of the multi-purpose OV1 spacecraft is a cylinder 4 ft 6.6 in long and 2 ft 3 in in diameter, with a cap on both ends covered with 5000 solar cells producing 22 Watts of power. The satellite is attached to a discardable propulsion module using an Altair 2 solid-fuelled motor for orbital insertion. It has two 1 ft 6 in antennae for command and telemetry, with attitude control provided by hydrogen peroxide thrusters. The use of a Sun sensor to determine the spacecraft's orientation to the Sun commenced with OV1-7, while OV1-13 and OV1-14 introduced advanced digital telemetry, which has improved the data return from the satellites.

OV1-1 undergoing a balance test prior to launch

Since the launch of OV1-1, on 21 January(GMT) 1965, 17 OV1 series satellites have so far been launched, with more apparently on the way. Only five have failed in some way. The basic purpose of this series is research into fundamental properties of the upper atmosphere and the space environment. This has meant that, unlike the experiments and results from most USAF satellites (and other OV series), which remain classified, the details of OV1 experiments have been published. But will we ever find out how closely the OV1 missions are related to the classified programs?

OV1 Highlights
Notable missions of the OV1 series so far have included OV1-4, launched 30 March (GMT) 1966, which carried three Tissue Equivalent Ionization Chambers, similar to one flown on Gemini 4, NASA’s first spacewalk mission. This data has helped to quantify the radiation hazard that astronauts face on long-duration missions in orbit.

OV1-6, launched on a Titan IIIC with the Manned Orbiting Laboratory test flight in November 1966, uniquely carried several inflatable balloons. Once ejected into orbit, they served as optical targets for ground-based observations, apparently to determine the value of inflatable decoys in confusing anti-missile systems.

PasComSat , or OV1-8, was launched on 14 July (GMT) 1966 and used for passive communications tests, designed to compare the advantages of a grid-sphere satellite against a balloon similar to the Echo series. Its non-standard design comprised a 30ft diameter open spherical grid of soft aluminium wires embedded in an inflatable plastic balloon. The entire satellite, with its unique propulsion module, weighed just 23lb. The satellite’s structure was also intended to demonstrate the feasibility of erecting an open grid structure in space, as the polybutyl methacrylate plastic of the balloon was designed to break down after a few days under the sun's strong ultraviolet rays, leaving the open aluminium structure in orbit. Tests indicate that the grid-satellite will remain in orbit for at least 11 years and have measured its reflective power as five times greater than that of a solid sphere.

OV1-9, launched in December 1966, carried a number of radiation experiments and was still aloft in late May 1967, during an intense period of solar and magnetic activity. Its data proved the existence of the Earth's electric field, which had long been theorised. OV1-10, OV1-9’s launch twin, returned the most comprehensive set of solar X-ray observations to date and also carried a cosmic ray telescope.

A unique “triple launch” took place on 27 July (GMT) 1967, with OV1-86 flying in a side-mounted pod and OV1-11 and OV1-12 positioned on top of the Atlas D launch vehicle. OV1-86 was an opportunistic mission composed of the unused satellite body originally intended as OV1-8, coupled with the unused OV1-6 propulsion module, which was not required for its Titan IIIC launch. The satellite carried a cosmic ray telescope, as well as equipment measuring the temperature radiation properties of different types of Earth terrain, mapping the Earth in the near-infrared spectrum. Although OV1-11 failed to orbit, OV1-12 carried the Flare Activated Radio-biological Observatory, equipped with a suite of eleven experiments to study the radiation hazard from solar flares.

The first Atlas F launch of the OV1 series placed OV1-13 and OV1-14 in orbit on 6 April (GMT) 1968. Both satellites were designed to focus on measuring radiation in space, although OV-14 ceased operating after one week in service. OV1-13 recently measured increases in the energy and intensity of electrons during a geomagnetic storm that took place 10 June 1968, and it is hoped that its data will shed light on how the particle flow caused by solar storms creates these high altitude increases.

OV1-14

Spades and Cannonballs
The most recent OV1 launch took place on 11 July, carrying both a standard satellite and the second non-standard spacecraft in this series. OV1-15 has a suite of experiments developed by The Aerospace Corporation designed to study the response of the upper atmosphere to solar and magnetospheric disturbances. It is hoped that the Solar Perturbation of Atmospheric Density Experiments Satellite (SPADES) group of complementary experiments will help to identify the cause of large and sudden fluctuations encountered in satellite trajectories, he ultimate goal being an ability to predict these fluctuations and their magnitude.

OV1-16 is another non-standard satellite, also known as LOADS (LOw Altitude Density Satellite) and Cannon Ball. This unique satellite is designed to have a large a mass/area ratio, so that they can remain in orbit at lower altitudes than conventional satellite, enabling measurements of the atmospheric properties at around 65-90miles altitude. This lower thermosphere region is a largely unknown part of the atmosphere. Cannon Ball lives up to its nickname, as a sphere with a diameter of only 24 inches, although its total weight is 600 lb, largely due to a 1.5 inch thick shell of brass! Concerns about heating by sunlight and atmospheric heating caused by orbiting at low altitude meant that the satellite body has been painted black (to increase radiation) with some gold-plated circular areas. If this experiment goes well, there may be further OV satellites of this type.

Unlucky So Far!
The OV2 series could be considered the “unluckiest” of the Orbiting Vehicle projects to date. Out of four flights, two have failed and two were canceled! The series was originally devised within the ARENTS (Advanced Research Environmental Test Satellite) programme, with the satellites intended to complement the Vela programme, monitoring for violations of the 1963 Partial Test Ban Treaty. However, with the cancellation of ARENTS, OV2 became something of an “orphan” series, its initial three satellites each tasked with quite different research.

OV2-1 shortly before launch, with its experiment package labelled

OV2-1, launched 15 October (GMT) 1965, was intended to monitor the biological hazards of near Earth charged particles, but failed to separate from its launcher. OV2-2, planned to conduct optical measurements from orbit, was cancelled, as was the OV2-4 satellite, added to the programme and designed to observe radiation from trans-lunar orbit. OV2-3, intended to undertake radiation studies, failed when contact was lost after launch on 21 December (GMT) 1965. A fifth OV2 satellite has been authorised and is due for launch later this year to conduct astronomical research and radiation studies.

Produced by Northrop and launched on Titan III test flights, the spin-stabilised OV2 satellites had cubic bodies made of aluminium honeycomb, approximately 2ft on a side. Attached to each of the four upper corners of the satellite are 7ft 6in paddle-like solar panels each carrying 20,160 solar cells, although the satellites also have Nickel-Cadmium to operate while in the Earth’s shadow.

Taking a Scout
In a departure from the earlier series, OV3 satellites have all been launched on Scout boosters, used with many civilian satellite programmes, such as the Explorer series. OV3-1 to OV3-4 were built by the Space General Corporation (part of Aerojet), while OV3-5 and 6 were constructed by the Air Force Cambridge Research Laboratory (AFCRL), which also managed the entire series.

Octagonal prisms in shape, the first four OV3 satellites were 2ft 5in in length and the same dimensions wide, with their experiments carried on long booms. With a design life-span of one year, the satellites were covered with 2560 solar cells. OV3-5 and OV3-6 were a little smaller than their predecessors, being only 1ft 9in in length.

The initial group of OV3-1 to 4 were devoted to radiation studies and launched across 1966. OV3-2 made important charged particle observations in conjunction with the 12 November 1966 South American solar eclipse that was also observed by Gemini 12. Other observations and auroral research were also co-ordinated with airborne observations by AFCRL KC-135 aircraft and sounding rocket flights by the National Research Council of Canada.

VLF receiver data from OV3-3 determined the location of the plasmapause (the outer boundary of the Earth's inner magnetosphere), while the satellite also carried out radiation studies using the same suite of instruments as the failed OV2-1. OV3-4 data contributed to the refinement of theoretical models of astronaut radiation dosage.

The final two OV3 missions, in 1967, were focussed on ionospheric research. While OV3-5 failed to achieve orbit, OV3-6, launched 5 December (GMT) 1967 was quite successful. Also known as Atmospheric Composition Satellite (ATCOS)-2, its data is being used to create more accurate atmospheric models.

Despite keeping costs low by using off-the-shelf components, the OV3 programme was phased out after OV3-6, in favour of the cheaper OV1 programme.

Whispering Galleries
Just as particular physical conditions create the “whispering gallery” phenomenon under the dome of a building, the OV4 series satellites was initially created to investigate long range radio propagation in the charged atmosphere of the ionosphere. Each OV4 launch was intended to consist of a pair of satellites, one being the transmitting spacecraft, the other a receiver. However, only the OV4-1 mission was flown in this way with the OV4-2 pair cancelled.

OV4-1R and OV4-1T shortly before launch

The OV4-1 satellite pair were both cylindrical, 1ft 5in in diameter, with domed upper ends. 2ft 11in long, they were powered by silver oxide/zinc batteries which gave them a 50-day lifespan.

Launched on a Manned Orbiting Laboratory (MOL) test flight on 3 November (GMT) 1966, OV4-1T carried a transmitter broadcasting on three frequencies in the 20-50 MHz range. To maximise its orbital separation from the OV4-1R receiver satellite, OV4-1T incorporated a small rocket motor. The two satellites were launched into slightly different 190-mile orbits, allowing them to test “whispering gallery” communications over a range of distances. This enabled the OV4-1 satellites to evaluate using the ionosphere's F layer as way to facilitate HF and VHF transmissions between satellites not in line of sight of each other.

Apart from being designated as part of the OV4 series, OV4-3 launched on the same Titan III flight as the OV4-1 pair, was a quite different spacecraft, being the boiler plate model of the Manned Orbiting Laboratory. The reconditioned Gemini 2 (originally flown on a sub-orbital flight on 19 January 1965), was attached to the MOL model.

Little Stars
The most recent of the Orbiting Vehicle programme to date, with the smallest satellites, the OV5 series is a continuation of the Air Force's earlier Environmental Research Satellite (ERS) series. OV5 satellites are upgraded versions of the original ERS satellites developed by Space Technology Laboratories (part of TRW Inc), modified with a command receiver, allowing instructions to be sent from the ground, and advanced digital telemetry.

Spin-stabilized, for improved communications and solar power reliability, OV5 series satellites are tetrahedral in shape and made of aluminium struts. Just under 1ft in width, each satellite carries 816 solar cells distributed over its eight triangular faces. Power is stored in a nickel–cadmium battery and experiments are mounted on the vertices of the tetrahedron.

Passive thermal control keeps the inside of the spacecraft at around 59 °F, and an on-board timer is designed to shut off each satellite after 18 months of operation. Telemetry is broadcast on frequencies compatible with NASA Spacecraft Tracking and Data Acquisition Network (STADAN) stations, enabling the satellite data to be received at multiple locations.

The first two OV5 satellites, OV5-1 and OV5-3 were launched on 28 April (GMT) 1967 on a Titan IIIC vehicle. OV5-1, also known as ERS 27 is an X-ray measuring microsatellite associated with the US Air Force's “space weather” prediction programme. OV5-3, also known as ERS 28, is a materials science research project, carrying a variety of metal samples and Teflon, to investigate how they are affected by long-term exposure to the space environment. OV5-2, another materials science research experiment, is due to be launched later this year.

While the Orbiting Vehicle programme has developed somewhat differently from the original concept, insofar as it has largely transitioned away from hitchhiking on various test launches, the OV1, 3 and 5 series satellites have demonstrated the value of using standardised designs as a means for cheap and relatively rapid development and launch of space research instruments. The OV1 and OV5 programmes look set to continue for some years to come and will hopefully contribute further significant data towards our understanding of the space environment.

So, here's to "micro" satellites–perhaps they presage the future of cheap space development!

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Science / Space Race

[January 24, 1968] On Track for the Moon (Apollo 5 and Surveyor 7]

January 24, 2023 Kaye Dee Leave a comment

by Kaye Dee

As we approach the first anniversary of the shocking loss of the crew of Apollo 1, the success of the recent Apollo 5 mission reminds us that the spirit of Grissom, White and Chaffee lives on as NASA continues developing and testing the technology to make a manned lunar landing a reality.

Apollo 1's Legacy
Although the fire that engulfed Apollo 1 and killed its crew destroyed its Command Module, the accident took place on the launchpad during a launch simulation, and fortunately the Saturn IB booster intended to loft that mission into orbit remained undamaged. Because that AS-204 vehicle was the last Saturn IB with full research and development instrumentation, NASA decided that this rocket would be re-assigned to Apollo 5, the much-delayed first test flight of the Lunar Module – the spacecraft essential for successfully landing astronauts on the Moon – while manned Apollo missions continue on hold.

From LEM to LM
The spacecraft we now call the Lunar Module (LM) became part of the Apollo programme in 1962, when NASA decided to adopt the technique of lunar orbit rendezvous (LOR) for its Moon landing missions. First proposed in 1919 by Ukrainian engineer and mathematician Yuri Kondratyuk, the LOR technique uses two spacecraft that travel together to the Moon and then separate in lunar orbit, with a lander carrying astronauts from orbit to the Moon’s surface. The LOR method allows the use of a smaller and lighter lander than the large, all-on-one spacecraft originally proposed for Apollo, and also provides for greater flexibility in landing site selection.

An early diagram comparing the size of a lunar landing vehicle using the Direct Ascent method of reaching the Moon and a LOR lunar excursion vehicle

The version of lunar orbit rendezvous suggested to NASA by engineer John C. Houbolt called for a landing vehicle consisting of two parts: a landing stage, that would accomplish the descent from orbit and remain on the Moon’s surface, and an ascent stage that would carry the astronauts back to the main spacecraft in orbit. This design gave us the Command Service Module as the Moon orbiting spacecraft, and what was originally called the Lunar Excursion Module (LEM, pronounced as a word, not as the individual letters) as the vehicle that would land astronauts on the Moon.

Dr. Houbolt illustrating the main spacecraft needed for his Lunar Orbit Rendezvous proposal for the Apollo programme

In June 1966, NASA changed the name to Lunar Module (LM), eliminating the word “excursion”. My friends at the WRE tell me that this was because there were concerns that using “excursion” might make it sound like the lunar missions were frivolous, and so reduce support for the Apollo programme! Despite the official name change, the astronauts, as well as staff at Grumman, still call it “the lem”, which certainly feels easier to say.

Delays…Delays…
However, the two-stage LEM/LM has proved much harder to develop and manufacture than the contractor Grumman originally anticipated, because of the complexity and level of reliability required of the hardware. Originally, NASA planned for the automated test flight of LM-1, the first Lunar Module, to occur in April 1967, but the delivery of the spacecraft was repeatedly delayed: the two stages of LM-1 did not arrive at Cape Kennedy until late June last year.

The separately-crated stages of LM-1 arriving at Kennedy Space Centre on board a Super Guppy cargo plane. The stages were mated to each other four days later

A team of 400 engineers and technicians then checked out the spacecraft to ensure that it met specifications. The discovery of leaks in the ascent stage propulsion system meant that the ascent and descent stages were demated and remated multiple times for repairs between August and October. LM-1 was finally mounted on its Saturn IB booster on 19 November and a launch date was set for the latter part of January 1968.

LM-1, encased in its SLA, being hoisted up for mounting on its launch vehicle

Lift Off at Last!

Although the launch was delayed for 10 hours when the countdown was held up by technical difficulties, Apollo 5 finally lifted off on 22 January 1968 (23 January for us here in Australia). The mission was designed to test the LM's descent and ascent propulsion systems, guidance and navigation systems, and the overall structural integrity of the craft. It also flight tested the Saturn V Instrument Unit.

Because they would not be needed during the Apollo 5 test flight, LM-1 had no landing legs, which helped to save weight. NASA also decided to replace the windows of LM-1 with aluminium plates as a precaution, after one of the windows broke during testing last December. Since the mission was of short duration, only some of LM-1’s systems were fully activated, and it only carried a partial load of consumables.

LM-1's "legless" configuration is clearly seen in this view of it during checkout at Kennedy Space Centre

The Apollo 5 flight did not include Command and Service Modules (CSM), or a launch escape tower, so pictures of the launch vehicle show it to look more like its predecessor AS-203 than AS-202, which tested the CSM. The Apollo 5 stack had an overall height of 180ft and weighed 1,299,434 lbs. The LM was contained within the Spacecraft Lunar Module Adapter (SLA), located just below the nose cap of the rocket. The SLA consists of four panels that open like petals once the nose cap is jettisoned in orbit, allowing the LM to separate from the launcher.

The Saturn IB worked perfectly, inserting the second stage and LM into an 88-by-120-nautical-mile orbit. After the nose cone was jettisoned, LM-1 coasted for 43 minutes 52 seconds, before separating from the SLA into a 90-by-120-nautical-mile orbit. NASA’s Carnarvon tracking station in Western Australia tracked the first six orbits of the mission, while the new Apollo tracking station at Honeysuckle Creek, near Canberra, followed LM-1’s first orbit.

Putting LM-1 Through its Paces
Since it had no astronaut crew, the LM-1 test flight had a mission programmer installed, which could control the craft remotely. The first planned 39-second descent-engine burn commenced after two orbits, only to be aborted by the Apollo Guidance Computer after just four seconds, as the spacecraft was not travelling at its expected velocity. Exactly why this occurred is now being investigated. Of course, if there had been a crew onboard, the astronauts would probably have been able to analyse the situation and decide whether the engine should be restarted.

Instead, Mission Control, under Flight Director Gene Kranz, decided to conduct the engine and "fire-in-the-hole" tests under manual control, as without these test firings the mission would be deemed a failure. The "fire in the hole" test verified that the ascent stage could fire while attached to the descent stage, a procedure that will be used to launch from the Moon’s surface, or in the event of an aborted lunar landing. It involves shutting down the descent stage, switching control and power to the ascent stage, and firing the ascent engine while the two stages are still mated.

Apollo 5 Flight Director Gene Kranz (right) with future Lunar Module crew Astronauts McDivitt (left) and Schweickart (centre) discussing LM-1's control issues

Both the ascent and descent engines were fired multiple times during the flight to demonstrate that they could be restarted after initial use. Eight hours into the mission, a problem with the guidance system did cause the ascent stage to spin out of control, but the vital engine test burns had been completed by then. LM-1 also demonstrated its ability to maintain a stable hover, and the guidance and navigation systems controlled the spacecraft's attitude and velocity as planned.

At the conclusion of the flight testing, the separated ascent and descent stages were left in a low orbit, with the anticipation that atmospheric drag would naturally cause their orbits to decay so that the craft would re-enter the atmosphere. The ascent stage re-entered and was destroyed on 24 January, but as I write the descent stage is still in orbit.

Another Step on the Road to the Moon
NASA considers that the LM performed well during its test flight, and have deemed Apollo 5 a success. One wonders now if the second unmanned test flight with LM-2, planned for later this year, will need to go ahead. NASA also plans to return astronauts to space with a test flight of the redesigned Command Module in September this year. Once that goal is accomplished, every part of the Apollo system will have been tested in spaceflight and it will finally be “Go!” for astronauts to shoot for the Moon. I can’t wait!

Lunar map showing the landing sites of all the successful Surveyor missions

So Long Surveyor!
As the Apollo programme powers forward, the last of NASA’s automated lunar exploration programmes is coming to an end, with Surveyor 7 now in operation on the Moon. The Surveyor project was developed with the goal of demonstrating the feasibility of soft landings on the Moon's surface, ensuring that it would be safe for Apollo crews to touch down in their Lunar Modules. The Surveyor landings have complemented the Lunar Orbiter programme (which drew to a close in the latter part of last year), which imaged the Moon from orbit, mapping the lunar surface and providing detailed photographs of many proposed Apollo landing sites.

Making It Safe for a LM Landing
Of the seven Surveyor missions, five achieved their objectives, returning valuable data and images from the lunar surface. Surveyor 1, launched on 30 May (US time) in 1966, was the first American spacecraft to soft land on the Moon (following the successful landing of the USSR’s Luna 9 on 31 January that year), returning 11,237 images of the lunar surface. Unfortunately, its successor, Surveyor 2, failed in September 1966, impacting onto the lunar surface when a malfunction of the guidance system caused an error in the mid-course correction as it travelled to the Moon.

Surveyor 1's panorama of the lunar surface, which captured its shadow, cast by the light of the Earth

Surveyor 3, which lifted off on 17 April 1967, was the first to conduct in-situ experiments on the lunar soil, using its extendable arm and scoop. The spacecraft also returned over 6,000 images, including the famous "Surveyors Footprint" shot, showing its footpad on the lunar surface. The probe had a lucky escape as it tried to land: a problem with its descent radar caused the descent engine to cut off late, resulting in the lander bouncing twice on the lunar surface before settling down to a final safe landing!

Surveyor 3's footprint and footpad on the lunar surface, showing how it bounced on landing. The extendable arm and scoop are visible on the left of the picture

Just three months later, in July, Surveyor 4 was not so lucky. After a textbook flight to the Moon, contact was lost with the spacecraft just 2.5 minutes before touchdown in the Sinus Medii (Central Bay) region and it crashed onto the lunar surface. It’s believed that the solid-fuel descent engine may have exploded.

Launched on 8 September, Surveyor 5 also encountered engine problems on descent to the lunar surface, with a leak in the spacecraft's thruster system. Fortunately, it survived to make a safe landing and returned over 20,000 photographs over three lunar days. Instead of a sampler arm, Surveyor 5 carried an alpha backscattering experiment, and had a bar magnet attached to one landing pad. It carried out the first off-Earth soil analysis and made one of the most significant finds of the Surveyor missions — that the Moon's surface is likely basaltic, and therefore suitably safe for human exploration.

Surveyor 5's alpha backscattering experiment, sometimes described as a chemical laboratory on the Moon

Surveyor 6 landed safely near the Surveyor 4 crash site in November 1967 carrying an instrument package virtually identical to Surveyor 5. The spacecraft transmitted a total of 30,027 detailed images of the lunar surface, as well as determining the abundance of the chemical elements in the lunar soil. As an additional experiment, Surveyor 6 carried out the first lift-off from the Moon. Its engines were restarted, lifting the probe 12 ft above the lunar surface, and moving it 8 ft to the west, after which it landed again safely, and continued its scientific programme.

Surveyor 7 – a Last Hurrah!
The successful completion of the Surveyor 6 mission accomplished all the goals that NASA had set for the Surveyor programme as an Apollo precursor. The JPL Surveyor team therefore decided that for the final mission they would aim for a riskier landing site, in the rugged highlands near the Tycho Crater. The engineers gave Surveyor 7 a less than 50-50 chance of landing upright due to the rough terrain in the area!

Tycho crater was the challenging landing site for NASA's last Surveyor mission

Launched on 7 January, Surveyor 7 is the last American robot spacecraft scheduled to land on the Moon before the Apollo astronauts. Its instrument package combines all the experiments used by its predecessors, in order to determine if the rugged terrain would be suitable for a future Apollo landing site.

During its first lunar day, the spacecraft’s camera has returned more than 14,000 images, including some views of the Earth! One of Surveyor 7’s innovations is the use of mirrors to obtain stereoscopic lunar photos. Laser beams directed at the Moon from two sites in the United States have also been recorded by cameras aboard Surveyor 7.

A view of the Earth captured by Surveyor 7's camera

Getting a Scoop
Surveyor 7’s versatile soil mechanics surface sampler is a key instrument on this mission. Designed to pick up lunar surface material, it can move samples around while being photographed, so that the properties of the lunar soil can be determined. It can also dig trenches up to 18 inches into the lunar surface to determine its bearing strength and squeeze lunar rocks or clods. The sampler is a scoop with a container which can be opened or closed by an electric motor. The scoop has a sharpened blade and includes two embedded magnets, to search for ferrous minerals and determine the magnetic characteristics of the lunar soil. So far, the moveable arm and scoop have performed 16 bearing tests, seven trenching tests, and two impact tests.

Only a few Surveyor 7 pictures are currently available, but this view of Surveyor 3 digging a trench into the Moon's surface shows how the scoop carries out this task

The scoop is mounted below the spacecraft’s the television camera so that it can reach the alpha-scattering instrument in its deployed position and move it to another selected location. In fact, the scoop helped to free the alpha-scattering instrument when it failed to deploy on the lunar surface. It has also been used to shade the alpha-scattering instrument and move it to different positions to evaluation other surface samples. During 36 hours of operation between January 11 and January 23, 1968, the sampler has performed flawlessly. Soil analyses have been conducted, as well as experiments on surface reflectivity and surface electrical properties.

Surveyor 7 is now “sleeping” through its first lunar night. If it survives this period of intense cold, hopefully it will continue to produce significant results during its next lunar day. But if it doesn’t, the scientists and engineers at NASA’s Jet Propulsion Laboratory are already describing the Surveyor programme as a “treasure house of information for landing a man on the Moon before the end of this decade”. This has to be a fitting epitaph for any space mission.

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Science / Space Race

[April 20, 1966] Space Exploration is Hard (Venera 2 and 3, Luna 10 and OAO 1)

April 20, 2021 Kaye Dee Leave a comment

by Kaye Dee

While manned spaceflight always grabs the headlines, the past month or so has seen some fascinating, if not always successful, attempts at planetary and lunar exploration and the launch of a new space observatory. The failures of some of these missions remind us that space exploration is hard and success is never guaranteed…

Still Unable to Lift the Veil of Venus

Launched just days apart back in November last year, Soviet Venus probes, Venera 2 and 3 were due to arrive at the Earth’s mysterious, cloud-veiled sister planet at the beginning of March, but both seem to have failed just on the verge of success.

As early as February 1961, the USSR commenced its attempts to explore Venus with the Venera (Russian for Venus) 1 probe. Although Venera-1 flew past Venus at a distance of 100,000km on 19 May 1961, no data were received, due to a communications failure. According to my friends at the Weapons Research Establishment, following that mission there may have been several failed attempts by the USSR to launch missions to Venus, before Venera 2 and 3 were successfully sent on their way back in November.

(top) Venera 1, the USSR's first Venus probe and (bottom) its official follow on, Venera 2. I wonder how many unannounced failures lie between these two missions?

According to various news releases from the Soviet news agency TASS, the two spacecraft were intended for different exploration missions. Venera 2 was planned to fly past the sunlit side of Venus and examine its enigmatic clouds. The spacecraft was equipped with cameras, a magnetometer and a variety of instruments to measure the radiation environment in space and at Venus. Valuable data on the interplanetary space environment was transmitted back to Earth during the flight to Venus.

All Venera 2's instruments were activated for the flyby on 27 February, at a distance of 14,790 miles. While the instruments were operating, the radio had to be shut down, with the probe storing their data in onboard recorders. The plan was for the stored data to be transmitted it to Earth once contact was restored. However, it seems that ground controllers in the USSR were unable to re-establish communications with the spacecraft after the flyby. Attempts to re-establish contact with Venera 2 ceased on March 4, but if communication with the spacecraft can be made at some future point, Soviet scientists believe that it may still be possible to recover some of the flyby data.

Touchdown?

Unlike Venera 2’s flyby (similar to those of Mariner 2 at Venus and Mariner 4 at Mars), Venera 3’s ambitious goal was to land a small capsule of instruments on the surface of Venus, hopefully to unlock at least some of the secrets hidden beneath its veil of clouds. Because some scientists believe there could be life on Venus, the USSR claims the lander was “sterilised” before its departure from Earth so that would not contaminate the Venusian atmosphere or surface with any microbial terrestrial life.

The Venera 3 lander was a metal sphere about 35 inches in diameter, which carried instruments to measure atmospheric temperature, pressure and composition, and light levels at different altitudes, as well small metal Soviet emblems. Interestingly, because some scientists still hold the view that Venus could be a water world, the lander was designed to be able to float and carried a motion detector, which could determine if it had actually landed in water and was rocking in the waves.

Venera 3 was similar to its sister-probe Venera 2. But look closely and you can see the landing capsule at the bottom of the spacecraft

Weighing 884lbs, the lander was designed to drop through Venus’ atmosphere on a parachute, transmitting data from its instruments directly back to Earth, while the rest of the Venera 3 spacecraft went into orbit around Venus to take other scientific measurements. However, like its sister probe, contact with Venera 3 was lost as it approached Venus. Tracking data indicates that the landing capsule entered the Venusian atmosphere on 1 March, although no telemetry was received from the lander. Nevertheless, the Venera 3 lander has become the first manmade object to impact another planet, which is an achievement in itself. The reasons for the failure of the two Venera spacecraft remain a mystery, although some experts believe that the thick Venusian atmosphere may have had something to do with it.

Newly-released Venera 3 stamp (thanks Uncle Ernie!). It shows the Soviet medal and pendant depicting the planet Earth that were carried on board the lander

Advancing the Soviet Lunar Programme

Despite the problems with its Venus programme, the USSR’s lunar programme seems to be going from strength to strength. Following on from the historic soft landing on the Moon with Luna 9 in February, Luna 10 marks another step forward, becoming the first spacecraft to go into orbit around the Moon. (Of course, it’s obvious that this feat was timed to occur during the 23rd Congress of the Communist Party of the Soviet Union, but I’m sure it was also deliberately planned to upstage the United States’ Lunar Orbiter program, which is due to commence later this year, with a series of spacecraft that will photograph and map the Moon in advance of the Apollo programme).

Luna 10, the first spacecraft to orbit the Moon

A pre-launch photograph of Luna 10 indicates that its design is very similar to that of Luna 9, although the instrument capsule on top has a different shape. Launched on 31 March, Luna 10 went into lunar orbit three days later. Its elliptical orbit approaches as close as to the lunar surface as 217 miles, with its farthest point at 632 miles, and takes just under three hours. The 530lb spacecraft is battery powered, rather than using solar panels, so it is unclear how long it will keep sending data back to the Earth, but at present it is producing a regular stream of information about the space environment in the vicinity of the Moon, that will help us understand how safe (or otherwise) it will be for the first cosmonauts and astronauts to explore cislunar space and the Moon itself.

Close up view of a model of the Luna 10 instrument capsule and the small Soviet metal pendants that it carried onboard

Scientific Instruments aboard Luna 10 include a gamma-ray spectrometer, a magnetometer, a meteorite detector, instruments for solar-plasma studies, and devices for measuring infrared emissions from the Moon and radiation conditions of the lunar environment. However, it is not clear whether the probe is actually carrying a camera to photograph the Moon’s surface. Preliminary data released by the Soviet Union indicates that there are higher concentrations of meteoritic dust in the vicinity of the Moon than in interplanetary space, as well as “electron fluxes” that are “70 to 100 times more intense than the cosmic ray background”.

First day cover commemorating the Luna 10 mission. Soviet space covers are masterpieces of propaganda, with the stamp design, envelope design and postmark all re-inforcing the message of Communist space achievement!

A Propaganda Serenade from the Moon!

As the Space Race heats up, the Soviet leadership is always ready to exploit propaganda opportunities associated with space exploration. To celebrate the CPSU Congress, a synthesised version of the Communist anthem “The Internationale” was broadcast live from Luna 10 to the congress on 4 April. (At least, it was claimed to be live: I wonder if Luna 10’s controllers actually used a pre-recorded version in case there were problems with the spacecraft? After all, it would be very politically embarrassing to have a failure of Soviet technology at such a high profile event for global Communism!)

Sky High Eyes on the Sky

The last mission I want to mention this month is NASA’s Orbiting Astronomical Observatory (OAO) 1, not least because this a major space project managed by a woman! Dr. Nancy Grace Roman, formerly a radio astronomer with the Naval Research Laboratory, joined NASA in 1959 and became Chief of Astronomy in NASA's Office of Space Science in 1960. She has a prestigious international reputation and was the first woman in an executive position at the space agency, where she has established the space astronomy programme.

Dr Nancy Grace Roman in 1962 with a model of another of her space observatory projects, the Orbiting Solar Observatory

The heaviest satellite yet launched by the United States (weighing almost two tons), OAO 1 was launched successfully on 8 April, riding to orbit on an Atlas-Agena D from Cape Canaveral. It carried 10 telescopes and other instruments capable of detecting ultraviolet, X-ray and gamma ray emissions to measure the absorption and emission characteristics of the stars, planets, nebulae from the visible to gamma-ray regions The observatory satellite was intended to give astronomers their first clear look at the heavens without the distorting effect of the Earth’s atmosphere and its results were greatly anticipated.

However, before the instruments could be activated, something caused a power failure that resulted in the mission being terminated after just 20 orbits. Because the spacecraft could not be controlled, its solar panels could not be deployed to recharge the batteries supplying the equipment and instruments on board the satellite. Although this is a blow to space astronomy, I’m sure the OAO programme will continue as future satellites are already in development.

NASA illustration of Orbiting Astronomical Observatory 1. While this satellite has failed, there will be future space observatories in this program

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Science / Space Race

[August 30, 1965] 8 Days or Bust! (Gemini 5's epic space mission)

August 30, 2020 Kaye Dee 3 Comments

by Kaye Dee

Mr. Barry McGuire should have waited another month to record his hit song Eve of Destruction. Why? Because then his telling line “You may leave Earth for four days in space, but when you return it’s the same old place” could have been made an even punchier by updating it with the latest space flight record of eight days, set by the crew of Gemini 5.

The Gemini 5 crew, Charles "Pete" Conrad (left) and mission commander Gordon "Gordo" Cooper (right), ready to set a new space endurance record

One for the Record Books

The safe return of the Gemini 5 crew yesterday, at the end of a mission dogged by technical problems, not only captured the record for the longest spaceflight to date, it has catapulted the United States into the lead ahead of the Soviet Union for the first time in the Space Race! From the outset, NASA planned for this mission to last eight days, to demonstrate that astronauts could live and work in space for the duration of an Apollo mission to the Moon and back. That this flight time beat the Soviet record of just under five days set by cosmonaut Valery Bykovsky in Vostok 5 in 1963, is a welcome added bonus. Other objectives of the mission included: demonstrating the guidance and control systems; evaluating the new fuel cell system and rendezvous radar; and testing the ability of the astronauts to manoeuvre close to another object.

A Mission Patch: the Start of a New Tradition?

For this crucial mission, NASA paired veteran Mercury astronaut Gordon Cooper, who flew America’s last and longest Mercury mission, with rookie Charles “Pete” Conrad, a member of the second group of astronauts selected in 1962. Because astronauts have been prohibited from naming their spacecraft (following NASA’s displeasure with the name Gus Grissom selected for Gemini 3), Cooper wanted to wear a mission insignia that would symbolise the purpose of their flight. He and Conrad designed a “mission patch”, along the lines of those worn by military units, showing a Conestoga wagon, the type of vehicle used by many of the pioneering families heading into the American West.

The Gemini 5 mission patch as Cooper and Conrad originally designed it, with its pioneer inspired motto (left), alongside the NASA-modified flight version on the right.

On their original design, the wagon carried a motto that was also derived from pioneering times: “8 Days or Bust”. But according to a rumour I’ve heard from my former WRE colleagues, NASA felt that this might leave the agency open to ridicule if the mission didn’t last that long. Because of this, the embroidered patches that Cooper and Conrad wore on their spacesuits during the flight had the ambitious slogan covered by a piece of cloth. But I like the idea of each mission having its own symbolic insignia, so I hope that mission patches become a tradition for future spaceflights.

Launching into History

Gemini 5 was originally supposed to launch on 19 August, but problems with the telemetry programmer and deteriorating weather delayed the lift-off until 21 August. Like previous Gemini missions, Cooper and Conrad lifted off from Launch Complex 39 at the Cape Kennedy Air Force Station. I understand that NASA will continue to use it for the rest of the Gemini programme while its new John F. Kennedy Space Centre is being constructed nearby for the Apollo missions.

During the launch, the astronauts experienced a type of vibration known as “pogo” (as in pogo stick!) which seems to have momentarily impaired their speech and vision. This will need to be further investigated to determine if it poses a threat to crew health and safety on future flights. After the launch, part of the Titan II launch vehicle's first stage was found floating on the surface of the Atlantic Ocean and retrieved; I expect it will go on display in a museum after it has been thoroughly studied.

Recovering the upper half of the Titan II launch vehicle first stage from the Atlantic Ocean

Dr. Rendezvous to the Rescue!

Just over 2 hours after launch, the Rendezvous Evaluation Pod (REP, nicknamed Little Rascal, I’m told) was ejected into orbit from Gemini 5. The crew were supposed to practice rendezvous techniques with this mini satellite. However, about 4 hours into the flight, very low oxygen pressure in one of the spacecraft’s fuel cells that provide onboard power led to a decision to shut both fuel cells down. Gemini 5 is the first mission to use this new method of generating onboard power, but without the fuel cells, the spacecraft has only a limited battery power reserve. As a result, Gemini 5 was powered down, drifting along in "chimp mode," without active control by the crew. It looked for a while as if the mission might be “2 days and bust”, but ground tests showed that the faulty fuel cell should work even with low oxygen pressure and both fuel cells were gradually put back into operation, enabling the mission to continue.

An artist's impression of the Gemini 5 Rendezvous Evaluation Pod, as the mission should have unfolded. Unfortunately, the battery on its flashing beacon, which helped the astronauts to see it against the blackness of space, died before the fuel cell issues were resolved.

The fuel cell failure meant that the REP experiment, and others, had to be scrapped. However, astronaut Edwin “Buzz” Aldrin devised a rendezvous simulation to test the Gemini 5 crew, which would require them to rendezvous with a specific point in space. The other astronauts don’t call Aldrin “Dr. Rendezvous” for nothing: he has a doctorate in Astronautics, specialising in orbital mechanics, from the Massachusetts Institute of Technology! The “phantom rendezvous” test took place on the third day of the mission. Cooper and Conrad proved that precision manoeuvres could be successfully accomplished, carrying out four different rendezvous manoeuvres using the Gemini’s Orbit Attitude and Manoeuvring System (OAMS).

On August 24 Cooper reached a cumulative total of 98 hours in space, over his two flights, taking the record for the longest time spent in space by an American astronaut. By the end of the mission he was the world record holder for time spent in space, leaving Bykovsky’s endurance record well behind!

Fuel Cells for Survival

A diagram showing the fuel cells installed on Gemini 5. Despite their problems on this mission, NASA expects to use fuel cells to provide electrical power and water on future space flights.

Another fuel cell problem surfaced on day four of the mission, but this was relatively minor, which was fortunate as the fuel cells not only produce electrical power for the Gemini spacecraft, but also provide the water supply for the crew. Like a battery, a fuel cell uses a chemical reaction to create an electric current. The Gemini fuel cell uses liquid oxygen and liquid hydrogen to generate electricity, which creates water as a by-product. Cooper and Conrad reported that the water had a lot of gas bubbles in it (with a predictable intestinal result!) and that it also had a taste they didn’t like. However, it was drinkable when mixed with Tang powdered orange drink, so I think that this will become a staple on future missions (a good advertising opportunity there!).

A plentiful supply of water also means that NASA will be able to provide the astronauts with more rehydratable foods from now on, although the Gemini 5 crew apparently did not have much of an appetite during the mission, only consuming about 1000 calories a day, instead of the planned 2700 calories.

Thanks to fuel cell-produced water, future NASA missions will have more rehydratable foods available. This sample Gemini meal includes a beef sandwich, strawberry cereal cubes, peaches, and beef and gravy. Astronauts use the water gun to reconstitute the food and scissors to open the packages

More Problems to Endure

The fifth day of the mission saw a major problem develop when one set of OAMS thrusters began to malfunction. This meant that all experiments where the thrusters needed to be used were cancelled. One cancellation was a great disappointment for us here in Australia. The Visual Acuity Test was designed to gauge the acuity of an astronaut’s vision from space, by observing patterns laid out on the ground.

Two test sites were prepared for this Gemini 5 experiment: one at Laredo, Texas and the other on Woodleigh sheep station (ranch), located about 90 miles south of Carnarvon, Western Australia. Carnarvon is the site of NASA’s largest tracking station outside the United States, combining both a Manned Space Flight Network facility and a Space Tracking and Data Acquisition Network station. At Woodleigh, piles of white sea-shells were bulldozed into carefully chosen patterns to determine the smallest pattern the astronauts could discern through the window of their spacecraft.

The Visual Acuity Test patterns at Woodleigh station seen from the air. Though they were composed of very white shells from a nearby beach, I think they might have been difficult to spot from space even under ideal conditions.

However, when this experiment should have been performed on 26 August, Gemini 5 was again drifting along powered down, due to the fuel cell and OAMS problems and could not maintain a stable view of the ground. The astronauts could see the smoke markers identifying the Woodleigh site but not the experimental patterns themselves due to the spacecraft's attitude. Attempts to view the site on later orbits were, unfortunately, no more successful, although the crew could see the lights of Carnarvon and Perth on night-time orbits.

During this powered-down period, Cooper and Conrad became quite cold and experienced feelings of disorientation caused by stars drifting past the windows as their capsule slowly rotated. Eventually, Cooper put covers on the windows to shut out the sight. Not only did they have difficulty sleeping, the crew also had to contend with persistent dandruff, apparently due to the low cabin humidity. The dry, flaky skin they shed settled everywhere, making for an unpleasant cabin environment. Even the instrument panels became partially obscured by dandruff!

No wonder the Gemini 5 crew found it difficult to sleep, when they were crowded together in a space about the same size as the front seat of a VW Beetle! Sleeping in alternate shifts was was not successful, but even sleeping at the same time did not make for a restful "night".

Although the mission’s technical problems caused some experiments to be cancelled, many others were still successfully carried out, including medical and photographic experiments. Among the crew's space science pictures were the first photographs of the zodiacal light and the gegenschein taken from orbit. Photographs of the Earth taken from space are also expected to produce detailed images that will have scientific, military and intelligence value once the films taken in flight are processed. I'm really looking forward to seeing them.

100 Orbits

On 28 August, Gemini 5 became the first manned spacecraft to complete 100 orbits of the Earth. In recognition of the achievement, Mission Control in Houston relayed 15 minutes of Dixieland music to the two astronauts, making Capcom Jim McDivitt the first space disc jockey! Because of the cancellation of experiments during the mission, Conrad had previously said he wished he had brought a book to read, or some music to listen to, and both Cooper and Conrad had expressed a preference for Dixieland music. Later that day, the Capcom at Houston also read up to the crew a little poem that Conrad’s wife, Jane, had written.

From Space to Shining Sea

A few hours before Gemini 5 returned to Earth yesterday, Gordon Cooper made a very special long-distance call – to fellow Mercury astronaut Scott Carpenter, who is living and working aboard the US Navy’s Sealab II facility, 205 feet beneath the surface of the Pacific Ocean near La Jolla, California. This radio call was apparently made to test the effectiveness of an undersea electronics lab installed on Sealab II, but it was also a nice piece of publicity for NASA and the Navy.

Mercury astronaut turned aquanaut Scott Carpenter, inside Sealab II, talks to Gordon Cooper aboard Gemini 5. Don't ask me how I got this photo!

Eight Days Without Busting!

Finally, on 29 August, at 190 hours, 27 minutes, and 43 seconds into the mission, retrofire commenced and Gemini 5 was on its way home. To demonstrate the level of control provided by the Gemini spacecraft design, the astronauts controlled their re-entry, rotating the capsule to create drag and lift. Unfortunately, due to an error by a computer programmer, Gemini 5 splashed down in the Atlantic Ocean 80 miles short of its target landing site, but the crew were quickly located and retrieved. Gemini 5 ended just a few hours short of the planned eight days, but the epic mission had come to a successful conclusion and lived up to its motto – it was most definitely not a bust!

Safely home! The crew of Gemini 5 look tired, but elated, after what what Conrad has described as "“eight days in a garbage can”. Notice those "censored" mission patches, whose motto was right after all!

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Galactic Journey

Tag Archives: Space Race

[May 14, 1970 Another Perfect Emergency (Saving Apollo-13)

[April 22, 1970] “Houston, We’ve had a Problem Here!” (Apollo-13 emergency in space)

[July 12, 1969] Paco Rabanne and the Theater of War

[July 16, 1968] Hitching a Ride to Orbit (Orbiting Vehicle Satellite Series)

[January 24, 1968] On Track for the Moon (Apollo 5 and Surveyor 7]

[April 20, 1966] Space Exploration is Hard (Venera 2 and 3, Luna 10 and OAO 1)

[August 30, 1965] 8 Days or Bust! (Gemini 5's epic space mission)

55 years ago: Science Fact and Fiction