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sbisson at 11:03am on 14/12/2002
sbisson at 11:03am on 14/12/2002...that the last men to walk on the moon began their long journey home.
So is it time to go back yet?
From the transcript at NASA:
188:01:27 Schmitt: Ten seconds.
188:01:28 Cernan: ...10 seconds.
188:01:29 LM Crew: Abort Stage.
188:01:30 Cernan: ...pushed. Engine Arm is Ascent.
188:01:32 Schmitt: Okay. I'm going to get the Pro. (Pause) 99 Proceeded 3, 2, 1...
188:01:39 Schmitt: Ignition.
[Schmitt - "As I recall, at the moment of ignition, all we had was static - loud static. And I was looking to see what happened, to see if I'd lost lock."]
[Cernan - "Jack spent half of the lift-off trying to get comm back."]
[Schmitt - "And I remember somebody telling me that what had happened was that they had a site handover scheduled right at lift-off! And nobody caught it."]
[Jack's memory is not quite accurate, although the problem was, in part, due to procedures on the ground. The following has been extracted from the Apollo 17 Mission 5-Day Report: "On lunar module ascent, two-way lock with the lunar module transponder was lost. This resulted in a 4-minute loss of uplink voice, and tracking data during ascent. It was necessary to have the Command Module Pilot pass comments from the ground to the lunar module crew during this period. The initial loss of lock was attributed to attenuation by the lunar module (engine) plume. Communications should have been re-established in less time (than 4 minutes). A review of data indicates that a normal re-acquisition by Goldstone should have been attempted earlier. Approximately 4 minutes after lunar module lift-off, a normal re-acquisition was accomplished."]
[According to Apollo 7 astronaut Walter Cunningham in his book "The All-American Boys" Gene's last words on the Moon were "Let's get this mother out of here." During the mission review in Santa Fe, Gene was surprised not to hear those words but it seems likely to me that what he was remembering was his "Now, let's get off." at 188:01:25 and that, in later tellings, the wording changed to the more colorful version Cunningham quotes. I have discussed this matter with Andrew Chaikin, who is another aficionado of the audio tapes, and we agree on the interpretation given here. My thanks to William Bianco for reminding me about this issue.]
188:01:40 Cernan: We're on our way, Houston!
So is it time to go back yet?
From the transcript at NASA:
188:01:27 Schmitt: Ten seconds.
188:01:28 Cernan: ...10 seconds.
188:01:29 LM Crew: Abort Stage.
188:01:30 Cernan: ...pushed. Engine Arm is Ascent.
188:01:32 Schmitt: Okay. I'm going to get the Pro. (Pause) 99 Proceeded 3, 2, 1...
188:01:39 Schmitt: Ignition.
[Schmitt - "As I recall, at the moment of ignition, all we had was static - loud static. And I was looking to see what happened, to see if I'd lost lock."]
[Cernan - "Jack spent half of the lift-off trying to get comm back."]
[Schmitt - "And I remember somebody telling me that what had happened was that they had a site handover scheduled right at lift-off! And nobody caught it."]
[Jack's memory is not quite accurate, although the problem was, in part, due to procedures on the ground. The following has been extracted from the Apollo 17 Mission 5-Day Report: "On lunar module ascent, two-way lock with the lunar module transponder was lost. This resulted in a 4-minute loss of uplink voice, and tracking data during ascent. It was necessary to have the Command Module Pilot pass comments from the ground to the lunar module crew during this period. The initial loss of lock was attributed to attenuation by the lunar module (engine) plume. Communications should have been re-established in less time (than 4 minutes). A review of data indicates that a normal re-acquisition by Goldstone should have been attempted earlier. Approximately 4 minutes after lunar module lift-off, a normal re-acquisition was accomplished."]
[According to Apollo 7 astronaut Walter Cunningham in his book "The All-American Boys" Gene's last words on the Moon were "Let's get this mother out of here." During the mission review in Santa Fe, Gene was surprised not to hear those words but it seems likely to me that what he was remembering was his "Now, let's get off." at 188:01:25 and that, in later tellings, the wording changed to the more colorful version Cunningham quotes. I have discussed this matter with Andrew Chaikin, who is another aficionado of the audio tapes, and we agree on the interpretation given here. My thanks to William Bianco for reminding me about this issue.]
188:01:40 Cernan: We're on our way, Houston!
sad
(no subject)
I get (2002-12-08 01:34:39 UT) - so I think that strictly speaking the anniversary is first thing tomorrow morning.
Unless the times in the transcript don't start from liftoff of course!
(no subject)
$ perl -MDate::Parse -le 'print scalar(gmtime(str2time("2002:12:07T05:33:00") + 188 *3600 + 60 + 39))'
Sun Dec 15 01:34:39 2002
(no subject)
(no subject)
universal time
n. Abbr. UT
The mean solar time for the meridian at Greenwich, England, used as a basis for calculating time throughout most of the world. Also called Greenwich time, Greenwich Mean Time, Zulu time.
(no subject)
12 noon should be when the Sun passes the meridian, right? But that depends where you are on Earth, so that's Local Solar Time.
All right, what about when the Sun passes the meridian at Greenwich? Well, the problem now is that the Earth's orbit is not perfectly circular, so if you try to set your clock by this you find it drifts by about +/- 15 minutes over the year (this is why sundials are usually a few minutes out). So instead there is a theoretical Mean Sun that is where the Sun would be if the Earth's orbit was perfectly circular. And the time defined by the Mean Sun crossing the meridian at Greenwich is Mean Solar Time, aka Greenwich Mean Time or UT (strictly UT1).
But atomic clocks these days are incredibly accurate and stable. Set one running and you'll find over several years that UT, as based on observation, is drifting off from actual clock time. This is because the Earth's rotation varies, so the Earth itself runs fast or slow buy a second every few years. But for really accurate time-based calculations, you want an absolutely stable time-base, so Ephemeris Time (ET), based on atomic clocks is used. ET (also termed Terrestrial Dynamical Time) is currently about a minute ahead of UT.
Finally, there is Coordinated Universal Time (UTC). If ET is 'true' time, then UT is continuously drifting from it at about a second every 2 or 3 years. This is a bit awkward, so instead UTC is locked to ET in the short term but slips by a whole 'leap second' whenever it gets more than 1s away from UT. UTC is what time signals are based on, and this is why every now and again the Greenwich time code has six 'pips' instead of five - that's a leap second being inserted.
This is almost certainly more than you ever wanted to know. In the unlikely event it isn't, this site explains further.
MC (defrocked Orbital Mechanic)
(no subject)
prevent any confusion. (;
Oh, and REBOL confirms the above perl code's correct...
>> 7-Dec-2002/05:33:00 + 188:01:39
== 15-Dec-2002/1:34:39
(:
The 188 hours is seven days and something, so that would seem
to make it from liftoff hour if my memory of it taking about a
week to get to the moon is correct.