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John Aaron

John Aaron is a astronomy topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand John Aaron rather than just read about it. In short: John W. Aaron (born 1943) is a former NASA engineer and was a flight controller during the Apollo program.

John Aaron — main illustration
John Aaron — illustration

Key takeaways

  • John Aaron belongs to astronomy; place it in that map before memorising details.
  • Learn the definition first, then one example that makes the definition concrete.
  • Connect John Aaron to a quantity you can measure, compute or draw — that is where exam questions come from.
  • Reproduce the core statement of John Aaron from memory before moving on to harder problems.

Reference excerpt

John W. Aaron (born 1943) is a former NASA engineer and was a flight controller during the Apollo program. He is widely credited with saving the Apollo 12 mission when it was struck by lightning soon after launch, and also played an important role during the Apollo 13 crisis.

Early life John Aaron was born in Wellington, Texas, and grew up in rural Western Oklahoma near Vinson, one of the youngest of a family of seven children. His mother was a minister, and his father was a cattle rancher. After spending a year attending Bethany Nazarene College, he transferred to Southwestern Oklahoma State University, from which he graduated in 1964 with a Bachelor of Science degree in Physics. Although he had intended to teach and ranch after graduating from college, he applied for a job with NASA on the recommendation of a friend.

NASA career

Gemini When he arrived at NASA, Aaron was trained as an EECOM, a flight controller with specific responsibility for the electrical, environmental and communications systems on board the spacecraft. By January 19, 1965, when the unmanned Gemini 2 was launched, he was already working in Mission Control as Chief EECOM Officer, which he did through 1967.

Apollo In 1967, Aaron became Chief EECOM Officer of the Command and Service Module in the Apollo program. In 1969, he moved on to serve as Section Head, Electrical Power, Electrical & Instrumentation Systems Section, a position he would hold for four years.

Apollo 12 On November 14, 1969, Aaron was on shift for the launch of Apollo 12. Thirty-six seconds after liftoff, the spacecraft was struck by lightning, causing a power surge. Instruments began to malfunction and telemetry data became garbled. The flight director, Gerry Griffin, expected that he would have to abort the mission. However, Aaron realized that he had previously seen this odd pattern of telemetry. A year before the flight, Aaron observed a test at Kennedy Space Center and noticed some unusual telemetry readings. On his own initiative, he traced this anomaly back to the obscure Signal Conditioning Electronics (SCE) system, and became one of the few flight controllers who was familiar with the system and its operations. For the case that first drew his attention to the system, normal readings could be restored by putting the SCE on its auxiliary setting, which meant that it would operate even with low-voltage conditions. Aaron surmised that this setting would also return the Apollo 12 telemetry to normal. When he made the call to the Flight Director, "Flight, EECOM. Try SCE to Aux", most of his mission control colleagues had no idea what he was talking about. Both the flight director and the CAPCOM Gerald P. Carr asked him to repeat the recommendation. Aaron repeated himself and Carr responded "What the hell's that?" Yet he relayed the order to the crew: "Apollo 12, Houston. Try SCE to auxiliary." Dick Gordon, a ground expert on the CSM as well as the Apollo 12 command module pilot, was familiar with both the location and the function of the SCE switch, and instructed Alan Bean to flip it to aux. Telemetry was immediately restored, allowing the mission to continue. This earned Aaron the lasting respect of his colleagues, who declared that he was a "steely-eyed missile man".

Apollo 13 Aaron was off duty when the Apollo 13 explosion occurred, but was quickly called to Mission Control to assist in the rescue and recovery effort. Flight Director Gene Kranz put Aaron in charge of the power supply budget. He was allowed to veto the ideas of other engineers, particularly when they affected the power usage of the modules. He was in charge of rationing the spacecraft's power during the return flight and, with help from grounded Apollo 13 crew member Ken Mattingly, devised an innovative power up sequence that allowed the Command Module to re-enter safely while operating on limited battery power. Contrary to existing procedures, he ordered the instrumentation system, which included telemetry, visibility, and the transmitters for communications, to be turned on last, just before reentry, rather than first. The call was a calculated risk. Without the instrumentation system, the crew and controllers would not know for certain if the cold startup had been successful until the last possible moment before reentry. However without the change, the capsule would have exhausted its battery supply before splashdown. The procedure was a success, and the crew was recovered safely.

Later career After the Apollo Lunar Surface program ended, Aaron remained at NASA in the Spacecraft Software Division. He became technical assistant to the chief in 1973, assistant chief in 1979, and chief in 1981. Beginning in 1984, he worked on Space Station Freedom project becoming manager of Johnson Space Center's space station projects office during 1989. On February 12, 1993, he was forced to resign from the job after Texas Senator Robert Krueger blamed him for $500 million of overspending on the station project. Aaron became a manager in Johnson Space Center's Engineering Directorate in 1993, and stayed in the directorate until he retired from NASA in 2000.

In film Aaron was portrayed by actor Loren Dean in the 1995 movie Apollo 13. Aaron was also played by John Travis in the 1998 mini-series From the Earth to the Moon. He was interviewed in the PBS documentary Apollo 13: To the Edge and Back, and in two History Channel documentaries about Mission Control, Failure Is Not an Option and Beyond the Moon: Failure Is Not an Option 2. The movie Apollo 13 takes a bit of literary license with the identity of NASA's "steely-eyed missile man". While Aaron's work on power management to help bring the spacecraft back to Earth is celebrated in the film, the moniker of the "steely-eyed missile man" is instead bestowed upon the head of the engineering team that devises a makeshift carbon dioxide filter to "fit a square peg in a round hole". That engineer was Ed Smylie, who was portrayed in the film as “Ted” by actor James Ritz. The 2015 science fiction film The Martian also contains a reference to a "steely-eyed missile man" at NASA (bestowed in that film upon the character Rich Purnell). The Legends of Tomorrow second-season episode "Moonshot" also includes a reference to that moniker, as does Season 5 Episode 8 of For All Mankind (TV series). In 2017, Aaron appeared in David Fairhead's documentary Mission Control: The Unsung Heroes of Apollo.

References

Illustrations

John Aaron illustration

Worked examples

Example 1 — a first encounter with John Aaron

Start with the simplest possible case. Write down what John Aaron claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In astronomy, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to John Aaron before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about John Aaron ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of John Aaron

In research
John Aaron appears in astronomy research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry
Engineering practice reuses John Aaron in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom
John Aaron is common in secondary-school and first-year university syllabi. It links to neighbouring topics 1943 births, Living people, Mayors of places in Texas, so understanding it makes those chapters shorter.
In everyday life
Look for John Aaron outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

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How to study John Aaron in 20 minutes

  1. Read the reference excerpt below once, without taking notes.
  2. Close the page and write down what John Aaron means in your own words.
  3. Compare your version with the excerpt and mark what you missed.
  4. Work through the three examples above with pen and paper.
  5. Explain John Aaron out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is John Aaron in simple terms?

John W. Aaron (born 1943) is a former NASA engineer and was a flight controller during the Apollo program.

Why does John Aaron matter?

Because it connects several astronomy ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study John Aaron?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on John Aaron.

Tags

  • 1943 births
  • Living people
  • Mayors of places in Texas
  • NASA flight controllers
  • People from Wellington, Texas
  • Southwestern Oklahoma State University alumni

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