Without evidence of benefit, an intervention should not be presumed to be beneficial or safe.

- Rogue Medic

What Does a Moon Landing ECG Look Like?


Some interesting ECG from the first people to land on the Moon.

During landing, they were running low on fuel and Buzz Aldrin appears to be showing signs of stress.


Click on images to make them larger.

The image above is from the following video describing the monitoring of the ECGs of the astronauts.


The reason this is in the news now is that one of four of the ECGs of Neil Armstrong as he stepped on the Moon was scheduled to be auctioned, but has been pulled due to questions about whether the owners have clear title to these items.[1]

How low on fuel were they? Were they going to crash?

They were just going to have to abort the mission and return to the Command Module, but after years of preparation for a Moon landing, that can be a huge amount of stress.


“EKG Recordings Taken as Apollo 11 Commander Neil Armstrong Took Man’s First Step on the Moon” and “4:13:24:28 Ground Elapsed Time.” Sheet is signed and inscribed in pencil, “To Paul Jones, The heartbeats that made this accomplishment possible as recorded at MCC on my console. Keep up your heart work. Charles A. Berry M.D.” Presentation also bears a Neil Armstrong autopen signature. Sheet is matted and framed with mission patches from Apollo 7, Apollo 8, Apollo 9, Apollo 10, Apollo 11, Apollo 12, Apollo 13, and two Snoopy patches, to an overall size of 20.75 x 24.75.[2]


Look at Buzz Aldrin’s ECG. The rate is about 400 BPM (Beats Per Minute).

Can a human heart beat that fast?

I have seen close to 300 BPM in a febrile infant.

Is the following rate possible for a human?


The rate is probably not possible.

The reason it looks so fast is most likely because the paper is being fed at a much slower speed than usual.

Conversely, we can get a better idea of what a very fast tachycardia looks like by speeding up the paper feed rate from the standard 25 mm/second to 50 mm/second or by manually pulling the paper through the printer faster than its normal rate.

EKG strip, six inches long, taken as Apollo 11 Commander Neil Armstrong took man’s first step on the moon. This is an actual strip of the EKG from Armstrong’s heart monitor at the moment he stepped onto the lunar surface.[2]



Compare that with a “six second section” of Buzz Aldrin’s ECG during their very low on fuel landing.


At 12.5 mm/second, this would be a rate of about 200 BPM, faster than the calculated maximum heart rate, but still capable of being a sinus tachycardia that is only associated with minor/moderate symptoms. At 10 mm/second, this would be a rate of about 160 BPM, which I regularly exceed (and recover from without any need for adenosine or cardioversion).


Several times you hear them checking with the flight surgeon and receiving a “Go,” each time. A heart rate of 400 should have resulted in something other than a “Go.” A few questions to Buzz Aldrin about how he is feeling would have been prudent.

If I have a patient with a heart rate of 400 and I do not ask a few questions about how the patient is doing, it would probably be because the patient is not capable of communicating. How are you feeling, hummingbird?

In general, sinus tachycardia is a response to other factors and, thus, it rarely (if ever) is the cause of instability in and of itself.[3]


At EMS 12 Lead, there is an excellent discussion of sinus tachycardia, and the nonsense of assuming that anything faster than 150 BPM is an SVT that needs adenosine or cardiversion.[4] This includes comments from Dr. John Mandrola and Dr. Mark Perrin.

Go read it.


[1] Neil Armstrong’s ‘Heartbeat,’ Apollo Joystick Pulled from Auction
by Robert Z. Pearlman, collectSPACE.com Editor
Date: 20 May 2013 Time: 04:34 PM ET

[2] Neil Armstrong’s Heartbeat – EKG Up For Auction
By Patrick Lockerby
May 5th 2013 04:20 PM
Science 2.0

[3] Overview
2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science
Part 8: Adult Advanced Cardiovascular Life Support
Part 8.3: Management of Symptomatic Bradycardia and Tachycardia
Free Full Text from Circulation.

[4] The Trouble With sinus Tachycardia
April 30, 2013
David Baumrind
EMS 12 Lead



  1. From the official NASA transcripts (http://www.hq.nasa.gov/alsj/a11/a11.landing.html)

    102:44:25 Armstrong (onboard): Gonna be right over that crater.

    102:44:26 Duke: Looks like SVT over a buck-fifty. I’m clear, you’re cl…

    102:44:27 Aldrin: Copy?

    102:44:28 Duke: Shocking!

    102:44:29 Armstrong (onboard): I got a good sp.. Aaaargh!

    102:44:30 Aldrin: What the (redacted)!