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peter eldergill
2009-Jul-20, 02:10 PM
From Phil's blog today


On July 20, 1969, at 20:17:40 GMT, human beings landed on an alien world. That was the moment that the Eagle lander touched down on the surface of the Moon, 40 years ago today. Nearly five hours later, at 02:56:15 GMT on July 21, Neil Armstrong placed his boot in the lunar regolith, planting it firmly into history as well.


Why did it take so long to step onto the moon after they landed? That's over 6 hours between the landing and climbing down.

Pete

slang
2009-Jul-20, 02:19 PM
No doubt someone will have a nice concise short explanation, but in the meantime you might enjoy browsing through the Apollo Lunar Surface Journal (http://history.nasa.gov/alsj/frame.html). Click Apollo 11, and near the bottom of the page you'll see a section called "Post-landing Activities", with lots of details.

NEOWatcher
2009-Jul-20, 02:21 PM
Why did it take so long to step onto the moon after they landed?
Preparation and rest period.
Lots of stuff to secure and stow/unstow. Plus; all that work done preparing for the landing and doing the work of the landing, it was safest to wait until they were rested from all that work.

WayneFrancis
2009-Jul-20, 02:29 PM
If memory serves me one of the things they where told to do after landing was to get some sleep...as if they'd be able to sleep after the physical rush of landing.

Rhaedas
2009-Jul-20, 02:42 PM
Good link, Slang. There was a lot going on even before they decided to go ahead with EVA preparation. After all, it's not like a car ride, where you just unbuckle and open the door. Look at a shuttle landing on Earth, they don't just come right out either, and they're at a familiar place.

kleindoofy
2009-Jul-20, 03:02 PM
... Why did it take so long to step onto the moon after they landed? That's over 6 hours between the landing and climbing down. ...
If memory serves me correctly, they actually went out *earlier* as originally planned.

They decided against the sleep they were supposed to take.

(What follows is from memory, so don't quote me, please)

As far as I know, the first period after landing was spent just deciding if it was safe for them to stay on the Moon's surface at all. It took a while to get the final "stay" command from Houston and they were prepared the whole time to do an immediate (emergency) start. They had to take as many quick photos and measurements as possible just in case they did have to make an emergency start.

After securing systems etc., it took them quite a while to put on the suits. Because of the tiny size of the LEM cabin, only one could do it at a time, while being assisted by the other. Bleeding the atmosphere out of the LEM cabin after they had their helmets on took another 3/4 of an hour, or so.

Then they had to find the key to the door ... ;)

Astaro
2009-Jul-21, 03:35 AM
It took a while to get the final "stay" command from Houston and they were prepared the whole time to do an immediate (emergency) start. They had to take as many quick photos and measurements as possible just in case they did have to make an emergency start.


My understanding is they had less than 2 minutes to make the 'stay/no-stay' decision, otherwise the command module would be too far ahead in its orbit and the Lunar module ascent stage wouldn't have enough fuel to catch up.

WayneFrancis
2009-Jul-21, 03:57 AM
I think the first then that was done after actually stepping on the moon was to collect a soil sample just in case :)

"Well boys, that was 1/4 million mile journey...looks nice but got to go!"

peter eldergill
2009-Jul-21, 03:58 PM
Thanks for the answers, folks (I didn't abandon the thread :) )

Pete

kleindoofy
2009-Jul-21, 07:54 PM
My understanding is they had less than 2 minutes to make the 'stay/no-stay' decision, ...
If I'm not mistaken, there were a number of 'stay/no-stay' decisions. One immediately after the landing, one 10-15 seconds later, one two minutes later, and a final one after one orbit of the CM. The LM was designed so that it could start at any time. A launch when the CM was farther away wouldn't really have been a problem, it just would have taken much longer to rendezvous.


I think the first then that was done after actually stepping on the moon was to collect a soil sample just in case ...
Yes, that was called the "contingency sample" and was put directly into a pouch on Armstong's leg. That way he couldn't drop it or lose it during an emergency retreat.

In fact, as I've always understood it, the entire time on the Moon's surface was planned more or less as one long emergency sequence. I.e., get things done in the order of highest priority, just in case you have to leave quickly and suddenly.

Swift
2009-Jul-21, 08:08 PM
In fact, as I've always understood it, the entire time on the Moon's surface was planned more or less as one long emergency sequence. I.e., get things done in the order of highest priority, just in case you have to leave quickly and suddenly.
I recall that whole "emergency sequence" plan from when I was a kid and watching it live. Looking back, it seems kind of silly and maybe a little quaint. But, at the time, the moon was one big unknown, and caution seemed sensible.