Apollo 13 was going to land in Complete Darkness ?

[Swamp Gas ?]

Had nothing gone wrong with Apollo 13, their lunar lander would have landed in complete darkness.

The Fra Mauro area on the moon with the April 14, 1970 moon phase shows the area of landing to be in complete darkness and by computation show that the area would not see the light of day until 88 hours later.

This means of course, that Apollo 13’s lunar lander must have had landing lights. ( can't find schematics showing this )

But why land in complete darkness?

Did they even intend to land ?

Odd !

[acey]

I understand that all the successful Apollo missions were on the Moon at a time of low sunlight. An overhead Sun would have led to them being exposed to too much radiation.

Are you sure you've got the exact landing site and expected landing time? Maybe they were meant to land just before lunar dawn.

[Psychobilly]

Perhaps they were planning on landing in darkness so that there would be less shadows for the conspiracy theorists...

[acey]

Apparently this idea was aired in a book called Dark Moon:

DARK MOON : Apollo and the Whistle-Blowers: David S, ARPS, Percy: Amazon.co.uk: Books

It was discussed in a Sky At Night programme in 2002 (about Apollo hoax theories) - there's a "rebuttal" here:

AULIS Online – Different Thinking

Issue seems to hinge on the exact intended landing time, and some possible confusion over it.

[661-pete]

I think the figures mentioned above are a bit out.

Apollo 13 was scheduled to land on the moon, IIRC, on April 16, not April 14. April 14 was the date (in GMT) when the oxygen tank exploded on the outward journey, still two days short of their destination, forcing the mission to abort. By April 16 the Fra Mauro region would have been in daylight.

But anyway, even for a night-time landing, there would have been plenty of earthlight. I don't think landing lights would have been necessary.

Did any of the Apollos land in Lunar night?

[beamish]

"Lunar surface touchdown is scheduled to take place at 9:55 p.m. EST April 15,"

From the NASA press pack 28th March 1970

below is a s/shot of the ephemeris generated by VMA

Karlo

[coliea]

An overhead Sun would have led to them being exposed to too much radiation.

Landing times were chosen when the sun was at a low angle to help the astronauts better discern topographic features i.e. hills, crater rims etc would cast shadows. A "mid-day" landing would have been more difficult as lunar features would have appeared flat - I don't think it had anything to do with radiation.

[Talitha]

From what I understand, the low-light angle landings were done for two reasons... visibility and temperature control. The low light angle would provide long shadows and enable the astronauts to choose a safe landing spot. The temperature of the lunar surface fluctuates phenomenally between lunar midnight and lunar noon and the temperature on the terminator would be mid-way between the two extremes, putting the least amount of strain on the astronauts' personal cooling systems.

[Swamp Gas ?]

Thanks for the replies and links.

The low light angles makes sense - as to discerning the surface features before landing.

The fact that there is still some dispute as to the planned landing time remains odd given the precision fuel/battery requirements of such missions.

Did the lander carry such landing lights and batteries in case of an emergency decent to the lunar surface in darkness ?

PS: I am not a conspiracy theorist - just intrigued by Apollos fine line between a missions success and failure - as was to befall this mission in particular.

[Tim]

Perhaps they were going to land by the light of chinese lanterns?

Like all good seat of your pants adventures, surely they just took a few sandwiches, a comic, and a couple of beers to tide them over, and flew on a wing and a prayer. Didn't you see the film? Jimmy's mom siad he could land a washing machine.

Besides, wasn't all this dealt with on the forum that you copied and pasted the words above from?

Any questions reports or opinions about telescopes/stargazing that we might be interested in, here in the astro-lounge?

TJ

[michaelmorris]

To the best of my knowledge none of the lunar modules carried landing lights. I cannot conceive of many circumstances where they would have carried out an 'emergency landing'. The weight and power constraints and the limitations imposed on mission profiles by orbital mechanics were so incredibly restrictive that I cannot imagine they would have put in equipment to cope with such a remote contigency.

If you want to find out about specific lunar missions I would suggest you read the series of mission reports by apogee books. Apogee Books Award Winning Space Series

For the history and much technical detail about the lunar module read Chariots for Apollo: The NASA History of Manned Lunar Spacecraft to 1969 Dover Books on Astronomy: Courtney G Brooks: Amazon.co.uk: Books

[Swamp Gas ?]

Thanks for the links Michael

[Swamp Gas ?]

Perhaps they were going to land by the light of chinese lanterns?

Ha Ha

Like all good seat of your pants adventures, surely they just took a few sandwiches, a comic, and a couple of beers to tide them over, and flew on a wing and a prayer. Didn't you see the film? Jimmy's mom siad he could land a washing machine.

Is that with or without landing lights ?

Besides, wasn't all this dealt with on the forum that you copied and pasted the words above from?

No - not satisfactorally - That is why I am looking for more informed opinion

Any questions reports or opinions about telescopes/stargazing that we might be interested in, here in the astro-lounge?

Yes - Is a 12" dobsonian large enough for Uranus or do I need to upgrade ?

TJ

....

[Tim]

Hmmm, I'm not certain sexual inuendo is allowed on the forum, i'll check and get back to you.

[Ant]

Not going anywhere.

Thread locked.