During Apollo 11 launch they said "Liftoff, we have a liftoff, 32 minutes past the hour", which is 01:32 p. m. or 13:32. This is UTC time, because Apollo 11 happened at 08:32 EST.

The question is: does NASA use UTC for other missions, or was Apollo program an exception?

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    $\begingroup$ "32 minutes past the hour" means exactly that: 32 minutes past whatever hour it currently is. I don't know how you are getting from this that it must be 13:32. It could be 12:32, 14:32, 20:32, it doesn't matter. XX:32 is 32 minutes past hour XX for any XX. $\endgroup$ Commented Dec 24, 2021 at 1:57
  • $\begingroup$ There's some discussion on time systems commonly used for spaceflight in How do launches avoid leap seconds? Why? $\endgroup$
    – Erin Anne
    Commented Dec 24, 2021 at 9:29
  • $\begingroup$ @JörgWMittag OK, how would one say "01:32" in English? Just "thirty two past one"? I've thought "thirty two past the hour" is just another way to say that. It's better to ask that at english.stackexchange.com $\endgroup$ Commented Dec 24, 2021 at 21:03

1 Answer 1


Note that "32 minutes past the hour" is true whether you are referring to Eastern Time or UTC. Just the "hour" is different.

Because a program references UTC, does not mean that other times are not used. The main reference time for Apollo was GET.

The term “GET” (Ground Elapsed Time), used for manned U.S. spaceflights prior to the Space Shuttle, was referenced to “Range Zero,” the last integral second before liftoff. With the first launch of the Shuttle, NASA began using the term “MET” (Mission Elapsed Time), which begins at the moment of solid rocket booster ignition.

Source https://history.nasa.gov/SP-4029/Apollo_00c_Introduction.htm

The ISS uses UTC but also local Houston and Moscow time. See the top bands in this example of the Onboard Short Term Plan Viewer

enter image description here

From What kind of time regiment/schedule do ISS astronauts have?


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