Why is the ladder of the LM always in the dark side of the LM?Importance of moon phases for Apollo missionsIs true that Armstrong was not designated as first to walk on the moon?Have there been any photos taken of a total Earth-Sun eclipse from the Moon, or its vicinity?Why does the side of the LEM look almost black in this photo? Did that cause problems?When Chang'e-3 landed on the moon, did LADEE notice?How did Apollo-12 manage to land next to Surveyor-3? First “Space-Tourists”?Any potential downside to throwing personal life support out the door on the Moon?Was there a technical reason why Apollo 10 didn't land on the moon?Why is the Apollo LEM ladder so far from the ground?
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Why is the ladder of the LM always in the dark side of the LM?
Importance of moon phases for Apollo missionsIs true that Armstrong was not designated as first to walk on the moon?Have there been any photos taken of a total Earth-Sun eclipse from the Moon, or its vicinity?Why does the side of the LEM look almost black in this photo? Did that cause problems?When Chang'e-3 landed on the moon, did LADEE notice?How did Apollo-12 manage to land next to Surveyor-3? First “Space-Tourists”?Any potential downside to throwing personal life support out the door on the Moon?Was there a technical reason why Apollo 10 didn't land on the moon?Why is the Apollo LEM ladder so far from the ground?
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margin-bottom:0;
.everyonelovesstackoverflowposition:absolute;height:1px;width:1px;opacity:0;top:0;left:0;pointer-events:none;
35
$begingroup$
When landed on the moon, the ladder seems to be in the shadow for each Apollo mission.
For example, on this photo, the ladder is not in the side exposed to the Sun. (the astronaut go out of the LM in the shadow of the LM).
Why did the NASA choose to land the LEM in that direction (exit (and the ladder) in the shadow of the LM)?
https://upload.wikimedia.org/wikipedia/commons/a/a5/AldrinOnMoon.jpg
lunar-landing lunar-module
edited Jul 8 at 10:43
Russell McMahon
7114 silver badges7 bronze badges
asked Jul 7 at 20:07
Manu HManu H
1,61314 silver badges34 bronze badges
$endgroup$
|
show 4 more comments
35
$begingroup$
When landed on the moon, the ladder seems to be in the shadow for each Apollo mission.
For example, on this photo, the ladder is not in the side exposed to the Sun. (the astronaut go out of the LM in the shadow of the LM).
Why did the NASA choose to land the LEM in that direction (exit (and the ladder) in the shadow of the LM)?
https://upload.wikimedia.org/wikipedia/commons/a/a5/AldrinOnMoon.jpg
lunar-landing lunar-module
edited Jul 8 at 10:43
Russell McMahon
7114 silver badges7 bronze badges
asked Jul 7 at 20:07
Manu HManu H
1,61314 silver badges34 bronze badges
$endgroup$
6
$begingroup$
Bonus: Whenever the Luna Rover is stationary the shadows of the sun-side wheels never fall on the far-side wheels. This is by design and not an astounding coincidence. [Somebody will probably now produce a photos falsifying this :-) , but that was the aim.]
$endgroup$
– Russell McMahon
Jul 8 at 6:53
3
$begingroup$
Bonus two: The shadow of the LEM is projected on both Aldrin and the lunar ground, why can't we see the ground?
$endgroup$
– qq jkztd
Jul 8 at 9:21
4
$begingroup$
@qqjkztd I think you lack some photographic background. It is not uncommon that the dynamic range of a camera make shadow dark enough to not be able to see details on it while white objects (the astronaut) light by a small reflector (here, the moon regolith) is bright enough to be seen (you can easily find reconstitution made with Lego on photographs' blogs and try to reproduce it yourself)
$endgroup$
– Manu H
Jul 8 at 9:27
4
$begingroup$
@qqjkztd This image shows the original plus a lightened version. I suspect that the black shadow has been further darkened - can't have original photos when they can be improved with editing. (I may be wrong). The 'black" is a very dark blue and is not quite homogeneous, but dies not have the variability I'd expect. [I often enough lighten up photos in this manner to check for editing]. || That said, the ground is horizontal and less liable to be highly illuminated by low angle reflected light.
$endgroup$
– Russell McMahon
Jul 8 at 10:43
8
$begingroup$
|| PhD thesis - Dynamic thermal modeling for moving objects on the Moon || p7 lower - ... During Apollo 14 the MET was used to transport instruments and equipment ... MET was designed to sustain minimal temperatures as low as 216 K. ... during surface operations one wheel fell below that threshold temperature only because it was shadowed by the other parts of the MET ... The Astronauts had to adopt to this unforeseen condition in order not to loose the MET. ... by positioning the MET Stack Overflow no shadow was casted on the wheels.
$endgroup$
– Russell McMahon
Jul 8 at 11:12
|
show 4 more comments
35
35
35
$begingroup$
When landed on the moon, the ladder seems to be in the shadow for each Apollo mission.
For example, on this photo, the ladder is not in the side exposed to the Sun. (the astronaut go out of the LM in the shadow of the LM).
Why did the NASA choose to land the LEM in that direction (exit (and the ladder) in the shadow of the LM)?
https://upload.wikimedia.org/wikipedia/commons/a/a5/AldrinOnMoon.jpg
lunar-landing lunar-module
edited Jul 8 at 10:43
Russell McMahon
7114 silver badges7 bronze badges
asked Jul 7 at 20:07
Manu HManu H
1,61314 silver badges34 bronze badges
$endgroup$
When landed on the moon, the ladder seems to be in the shadow for each Apollo mission.
For example, on this photo, the ladder is not in the side exposed to the Sun. (the astronaut go out of the LM in the shadow of the LM).
Why did the NASA choose to land the LEM in that direction (exit (and the ladder) in the shadow of the LM)?
https://upload.wikimedia.org/wikipedia/commons/a/a5/AldrinOnMoon.jpg
lunar-landing lunar-module
lunar-landing lunar-module
edited Jul 8 at 10:43
Russell McMahon
7114 silver badges7 bronze badges
asked Jul 7 at 20:07
Manu HManu H
1,61314 silver badges34 bronze badges
edited Jul 8 at 10:43
Russell McMahon
7114 silver badges7 bronze badges
asked Jul 7 at 20:07
Manu HManu H
1,61314 silver badges34 bronze badges
edited Jul 8 at 10:43
Russell McMahon
7114 silver badges7 bronze badges
edited Jul 8 at 10:43
Russell McMahon
7114 silver badges7 bronze badges
edited Jul 8 at 10:43
Russell McMahon
7114 silver badges7 bronze badges
7114 silver badges7 bronze badges
asked Jul 7 at 20:07
Manu HManu H
1,61314 silver badges34 bronze badges
asked Jul 7 at 20:07
Manu HManu H
1,61314 silver badges34 bronze badges
asked Jul 7 at 20:07
Manu HManu H
1,61314 silver badges34 bronze badges
1,61314 silver badges34 bronze badges
6
$begingroup$
Bonus: Whenever the Luna Rover is stationary the shadows of the sun-side wheels never fall on the far-side wheels. This is by design and not an astounding coincidence. [Somebody will probably now produce a photos falsifying this :-) , but that was the aim.]
$endgroup$
– Russell McMahon
Jul 8 at 6:53
3
$begingroup$
Bonus two: The shadow of the LEM is projected on both Aldrin and the lunar ground, why can't we see the ground?
$endgroup$
– qq jkztd
Jul 8 at 9:21
4
$begingroup$
@qqjkztd I think you lack some photographic background. It is not uncommon that the dynamic range of a camera make shadow dark enough to not be able to see details on it while white objects (the astronaut) light by a small reflector (here, the moon regolith) is bright enough to be seen (you can easily find reconstitution made with Lego on photographs' blogs and try to reproduce it yourself)
$endgroup$
– Manu H
Jul 8 at 9:27
4
$begingroup$
@qqjkztd This image shows the original plus a lightened version. I suspect that the black shadow has been further darkened - can't have original photos when they can be improved with editing. (I may be wrong). The 'black" is a very dark blue and is not quite homogeneous, but dies not have the variability I'd expect. [I often enough lighten up photos in this manner to check for editing]. || That said, the ground is horizontal and less liable to be highly illuminated by low angle reflected light.
$endgroup$
– Russell McMahon
Jul 8 at 10:43
8
$begingroup$
|| PhD thesis - Dynamic thermal modeling for moving objects on the Moon || p7 lower - ... During Apollo 14 the MET was used to transport instruments and equipment ... MET was designed to sustain minimal temperatures as low as 216 K. ... during surface operations one wheel fell below that threshold temperature only because it was shadowed by the other parts of the MET ... The Astronauts had to adopt to this unforeseen condition in order not to loose the MET. ... by positioning the MET Stack Overflow no shadow was casted on the wheels.
$endgroup$
– Russell McMahon
Jul 8 at 11:12
|
show 4 more comments
6
$begingroup$
Bonus: Whenever the Luna Rover is stationary the shadows of the sun-side wheels never fall on the far-side wheels. This is by design and not an astounding coincidence. [Somebody will probably now produce a photos falsifying this :-) , but that was the aim.]
$endgroup$
– Russell McMahon
Jul 8 at 6:53
3
$begingroup$
Bonus two: The shadow of the LEM is projected on both Aldrin and the lunar ground, why can't we see the ground?
$endgroup$
– qq jkztd
Jul 8 at 9:21
4
$begingroup$
@qqjkztd I think you lack some photographic background. It is not uncommon that the dynamic range of a camera make shadow dark enough to not be able to see details on it while white objects (the astronaut) light by a small reflector (here, the moon regolith) is bright enough to be seen (you can easily find reconstitution made with Lego on photographs' blogs and try to reproduce it yourself)
$endgroup$
– Manu H
Jul 8 at 9:27
4
$begingroup$
@qqjkztd This image shows the original plus a lightened version. I suspect that the black shadow has been further darkened - can't have original photos when they can be improved with editing. (I may be wrong). The 'black" is a very dark blue and is not quite homogeneous, but dies not have the variability I'd expect. [I often enough lighten up photos in this manner to check for editing]. || That said, the ground is horizontal and less liable to be highly illuminated by low angle reflected light.
$endgroup$
– Russell McMahon
Jul 8 at 10:43
8
$begingroup$
|| PhD thesis - Dynamic thermal modeling for moving objects on the Moon || p7 lower - ... During Apollo 14 the MET was used to transport instruments and equipment ... MET was designed to sustain minimal temperatures as low as 216 K. ... during surface operations one wheel fell below that threshold temperature only because it was shadowed by the other parts of the MET ... The Astronauts had to adopt to this unforeseen condition in order not to loose the MET. ... by positioning the MET Stack Overflow no shadow was casted on the wheels.
$endgroup$
– Russell McMahon
Jul 8 at 11:12
6
6
$begingroup$
Bonus: Whenever the Luna Rover is stationary the shadows of the sun-side wheels never fall on the far-side wheels. This is by design and not an astounding coincidence. [Somebody will probably now produce a photos falsifying this :-) , but that was the aim.]
$endgroup$
– Russell McMahon
Jul 8 at 6:53
$begingroup$
Bonus: Whenever the Luna Rover is stationary the shadows of the sun-side wheels never fall on the far-side wheels. This is by design and not an astounding coincidence. [Somebody will probably now produce a photos falsifying this :-) , but that was the aim.]
$endgroup$
– Russell McMahon
Jul 8 at 6:53
3
3
$begingroup$
Bonus two: The shadow of the LEM is projected on both Aldrin and the lunar ground, why can't we see the ground?
$endgroup$
– qq jkztd
Jul 8 at 9:21
$begingroup$
Bonus two: The shadow of the LEM is projected on both Aldrin and the lunar ground, why can't we see the ground?
$endgroup$
– qq jkztd
Jul 8 at 9:21
4
4
$begingroup$
@qqjkztd I think you lack some photographic background. It is not uncommon that the dynamic range of a camera make shadow dark enough to not be able to see details on it while white objects (the astronaut) light by a small reflector (here, the moon regolith) is bright enough to be seen (you can easily find reconstitution made with Lego on photographs' blogs and try to reproduce it yourself)
$endgroup$
– Manu H
Jul 8 at 9:27
$begingroup$
@qqjkztd I think you lack some photographic background. It is not uncommon that the dynamic range of a camera make shadow dark enough to not be able to see details on it while white objects (the astronaut) light by a small reflector (here, the moon regolith) is bright enough to be seen (you can easily find reconstitution made with Lego on photographs' blogs and try to reproduce it yourself)
$endgroup$
– Manu H
Jul 8 at 9:27
4
4
$begingroup$
@qqjkztd This image shows the original plus a lightened version. I suspect that the black shadow has been further darkened - can't have original photos when they can be improved with editing. (I may be wrong). The 'black" is a very dark blue and is not quite homogeneous, but dies not have the variability I'd expect. [I often enough lighten up photos in this manner to check for editing]. || That said, the ground is horizontal and less liable to be highly illuminated by low angle reflected light.
$endgroup$
– Russell McMahon
Jul 8 at 10:43
$begingroup$
@qqjkztd This image shows the original plus a lightened version. I suspect that the black shadow has been further darkened - can't have original photos when they can be improved with editing. (I may be wrong). The 'black" is a very dark blue and is not quite homogeneous, but dies not have the variability I'd expect. [I often enough lighten up photos in this manner to check for editing]. || That said, the ground is horizontal and less liable to be highly illuminated by low angle reflected light.
$endgroup$
– Russell McMahon
Jul 8 at 10:43
8
8
$begingroup$
|| PhD thesis - Dynamic thermal modeling for moving objects on the Moon || p7 lower - ... During Apollo 14 the MET was used to transport instruments and equipment ... MET was designed to sustain minimal temperatures as low as 216 K. ... during surface operations one wheel fell below that threshold temperature only because it was shadowed by the other parts of the MET ... The Astronauts had to adopt to this unforeseen condition in order not to loose the MET. ... by positioning the MET Stack Overflow no shadow was casted on the wheels.
$endgroup$
– Russell McMahon
Jul 8 at 11:12
$begingroup$
|| PhD thesis - Dynamic thermal modeling for moving objects on the Moon || p7 lower - ... During Apollo 14 the MET was used to transport instruments and equipment ... MET was designed to sustain minimal temperatures as low as 216 K. ... during surface operations one wheel fell below that threshold temperature only because it was shadowed by the other parts of the MET ... The Astronauts had to adopt to this unforeseen condition in order not to loose the MET. ... by positioning the MET Stack Overflow no shadow was casted on the wheels.
$endgroup$
– Russell McMahon
Jul 8 at 11:12
|
show 4 more comments
1 Answer
1
active
oldest
votes
77
$begingroup$
All the lunar landings were performed with the sun low in the sky behind the LM, between 5º and 14º above the horizon at the landing site. This provided several advantages:
- The sun wouldn't be in the crew’s eyes during any portion of the descent (they’d start out oriented feet forward, lying on their backs looking upward, during the braking phase, and progressively pitch downward from that orientation to standing vertically looking forward during the final portion of descent)
- The terrain would cast sharp shadows, which made it easier to see the shape of the surface
- The shadow of the LM itself would be cast on the ground ahead in the final moments of descent, which would help the commander judge the LM's altitude.
The descent ladder, being on the front leg of the ship, was therefore always in shadow after touchdown.
answered Jul 7 at 21:39
Russell BorogoveRussell Borogove
106k5 gold badges376 silver badges459 bronze badges
$endgroup$
12
$begingroup$
The third bullet point there is the key one - pilots would rather use shadows to judge altitude rather than blindly trusting doppler radar to indicate the descent rate and altitude of the LM. From what I've read, no landing was ever performed under autonomous control. Lovell intended to, but of course that never happened. It make sense for the ladder to be under the only windows on the ascent stage - ergo the ladder is on the dark side.
$endgroup$
– Snow
Jul 8 at 10:42
7
$begingroup$
@Snow: That was my thinking exactly, from KSP landings. I always use the shadow.
$endgroup$
– dotancohen
Jul 8 at 11:22
4
$begingroup$
The cabin was very small, and the astronauts stood just behind the window to improve their downward view. There was nowhere else for the exit hatch to be placed.
$endgroup$
– Russell Borogove
Jul 8 at 13:00
6
$begingroup$
The low sun makes a lot of sense from the point of view of revealing surface relief during the descent. This meant the landing had to be made in the lunar morning or evening. Morning was always chosen because, in the event of any mishap, that gave them the maximum amount of daylight to resolve the issue.
$endgroup$
– Oscar Bravo
Jul 8 at 13:50
6
$begingroup$
@CGCampbell, it still makes sense to want to maximize the amount of daylight in case of a problem, even when the period from dawn to dusk lasts 348 hours. I'd rather have 324 hours to work on something if I'm stranded on another world, than just 24 hours. (Or rather, I'd prefer my useful working period to be determined by O2, and not daylight.)
$endgroup$
– Ghedipunk
Jul 8 at 17:42
|
show 10 more comments
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1 Answer
1
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oldest
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oldest
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active
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votes
77
$begingroup$
All the lunar landings were performed with the sun low in the sky behind the LM, between 5º and 14º above the horizon at the landing site. This provided several advantages:
- The sun wouldn't be in the crew’s eyes during any portion of the descent (they’d start out oriented feet forward, lying on their backs looking upward, during the braking phase, and progressively pitch downward from that orientation to standing vertically looking forward during the final portion of descent)
- The terrain would cast sharp shadows, which made it easier to see the shape of the surface
- The shadow of the LM itself would be cast on the ground ahead in the final moments of descent, which would help the commander judge the LM's altitude.
The descent ladder, being on the front leg of the ship, was therefore always in shadow after touchdown.
answered Jul 7 at 21:39
Russell BorogoveRussell Borogove
106k5 gold badges376 silver badges459 bronze badges
$endgroup$
12
$begingroup$
The third bullet point there is the key one - pilots would rather use shadows to judge altitude rather than blindly trusting doppler radar to indicate the descent rate and altitude of the LM. From what I've read, no landing was ever performed under autonomous control. Lovell intended to, but of course that never happened. It make sense for the ladder to be under the only windows on the ascent stage - ergo the ladder is on the dark side.
$endgroup$
– Snow
Jul 8 at 10:42
7
$begingroup$
@Snow: That was my thinking exactly, from KSP landings. I always use the shadow.
$endgroup$
– dotancohen
Jul 8 at 11:22
4
$begingroup$
The cabin was very small, and the astronauts stood just behind the window to improve their downward view. There was nowhere else for the exit hatch to be placed.
$endgroup$
– Russell Borogove
Jul 8 at 13:00
6
$begingroup$
The low sun makes a lot of sense from the point of view of revealing surface relief during the descent. This meant the landing had to be made in the lunar morning or evening. Morning was always chosen because, in the event of any mishap, that gave them the maximum amount of daylight to resolve the issue.
$endgroup$
– Oscar Bravo
Jul 8 at 13:50
6
$begingroup$
@CGCampbell, it still makes sense to want to maximize the amount of daylight in case of a problem, even when the period from dawn to dusk lasts 348 hours. I'd rather have 324 hours to work on something if I'm stranded on another world, than just 24 hours. (Or rather, I'd prefer my useful working period to be determined by O2, and not daylight.)
$endgroup$
– Ghedipunk
Jul 8 at 17:42
|
show 10 more comments
77
$begingroup$
All the lunar landings were performed with the sun low in the sky behind the LM, between 5º and 14º above the horizon at the landing site. This provided several advantages:
- The sun wouldn't be in the crew’s eyes during any portion of the descent (they’d start out oriented feet forward, lying on their backs looking upward, during the braking phase, and progressively pitch downward from that orientation to standing vertically looking forward during the final portion of descent)
- The terrain would cast sharp shadows, which made it easier to see the shape of the surface
- The shadow of the LM itself would be cast on the ground ahead in the final moments of descent, which would help the commander judge the LM's altitude.
The descent ladder, being on the front leg of the ship, was therefore always in shadow after touchdown.
answered Jul 7 at 21:39
Russell BorogoveRussell Borogove
106k5 gold badges376 silver badges459 bronze badges
$endgroup$
12
$begingroup$
The third bullet point there is the key one - pilots would rather use shadows to judge altitude rather than blindly trusting doppler radar to indicate the descent rate and altitude of the LM. From what I've read, no landing was ever performed under autonomous control. Lovell intended to, but of course that never happened. It make sense for the ladder to be under the only windows on the ascent stage - ergo the ladder is on the dark side.
$endgroup$
– Snow
Jul 8 at 10:42
7
$begingroup$
@Snow: That was my thinking exactly, from KSP landings. I always use the shadow.
$endgroup$
– dotancohen
Jul 8 at 11:22
4
$begingroup$
The cabin was very small, and the astronauts stood just behind the window to improve their downward view. There was nowhere else for the exit hatch to be placed.
$endgroup$
– Russell Borogove
Jul 8 at 13:00
6
$begingroup$
The low sun makes a lot of sense from the point of view of revealing surface relief during the descent. This meant the landing had to be made in the lunar morning or evening. Morning was always chosen because, in the event of any mishap, that gave them the maximum amount of daylight to resolve the issue.
$endgroup$
– Oscar Bravo
Jul 8 at 13:50
6
$begingroup$
@CGCampbell, it still makes sense to want to maximize the amount of daylight in case of a problem, even when the period from dawn to dusk lasts 348 hours. I'd rather have 324 hours to work on something if I'm stranded on another world, than just 24 hours. (Or rather, I'd prefer my useful working period to be determined by O2, and not daylight.)
$endgroup$
– Ghedipunk
Jul 8 at 17:42
|
show 10 more comments
77
77
77
$begingroup$
All the lunar landings were performed with the sun low in the sky behind the LM, between 5º and 14º above the horizon at the landing site. This provided several advantages:
- The sun wouldn't be in the crew’s eyes during any portion of the descent (they’d start out oriented feet forward, lying on their backs looking upward, during the braking phase, and progressively pitch downward from that orientation to standing vertically looking forward during the final portion of descent)
- The terrain would cast sharp shadows, which made it easier to see the shape of the surface
- The shadow of the LM itself would be cast on the ground ahead in the final moments of descent, which would help the commander judge the LM's altitude.
The descent ladder, being on the front leg of the ship, was therefore always in shadow after touchdown.
answered Jul 7 at 21:39
Russell BorogoveRussell Borogove
106k5 gold badges376 silver badges459 bronze badges
$endgroup$
All the lunar landings were performed with the sun low in the sky behind the LM, between 5º and 14º above the horizon at the landing site. This provided several advantages:
- The sun wouldn't be in the crew’s eyes during any portion of the descent (they’d start out oriented feet forward, lying on their backs looking upward, during the braking phase, and progressively pitch downward from that orientation to standing vertically looking forward during the final portion of descent)
- The terrain would cast sharp shadows, which made it easier to see the shape of the surface
- The shadow of the LM itself would be cast on the ground ahead in the final moments of descent, which would help the commander judge the LM's altitude.
The descent ladder, being on the front leg of the ship, was therefore always in shadow after touchdown.
answered Jul 7 at 21:39
Russell BorogoveRussell Borogove
106k5 gold badges376 silver badges459 bronze badges
edited Jul 7 at 22:23
answered Jul 7 at 21:39
Russell BorogoveRussell Borogove
106k5 gold badges376 silver badges459 bronze badges
answered Jul 7 at 21:39
Russell BorogoveRussell Borogove
106k5 gold badges376 silver badges459 bronze badges
answered Jul 7 at 21:39
Russell BorogoveRussell Borogove
106k5 gold badges376 silver badges459 bronze badges
106k5 gold badges376 silver badges459 bronze badges
12
$begingroup$
The third bullet point there is the key one - pilots would rather use shadows to judge altitude rather than blindly trusting doppler radar to indicate the descent rate and altitude of the LM. From what I've read, no landing was ever performed under autonomous control. Lovell intended to, but of course that never happened. It make sense for the ladder to be under the only windows on the ascent stage - ergo the ladder is on the dark side.
$endgroup$
– Snow
Jul 8 at 10:42
7
$begingroup$
@Snow: That was my thinking exactly, from KSP landings. I always use the shadow.
$endgroup$
– dotancohen
Jul 8 at 11:22
4
$begingroup$
The cabin was very small, and the astronauts stood just behind the window to improve their downward view. There was nowhere else for the exit hatch to be placed.
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– Russell Borogove
Jul 8 at 13:00
6
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The low sun makes a lot of sense from the point of view of revealing surface relief during the descent. This meant the landing had to be made in the lunar morning or evening. Morning was always chosen because, in the event of any mishap, that gave them the maximum amount of daylight to resolve the issue.
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– Oscar Bravo
Jul 8 at 13:50
6
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@CGCampbell, it still makes sense to want to maximize the amount of daylight in case of a problem, even when the period from dawn to dusk lasts 348 hours. I'd rather have 324 hours to work on something if I'm stranded on another world, than just 24 hours. (Or rather, I'd prefer my useful working period to be determined by O2, and not daylight.)
$endgroup$
– Ghedipunk
Jul 8 at 17:42
|
show 10 more comments
12
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The third bullet point there is the key one - pilots would rather use shadows to judge altitude rather than blindly trusting doppler radar to indicate the descent rate and altitude of the LM. From what I've read, no landing was ever performed under autonomous control. Lovell intended to, but of course that never happened. It make sense for the ladder to be under the only windows on the ascent stage - ergo the ladder is on the dark side.
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– Snow
Jul 8 at 10:42
7
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@Snow: That was my thinking exactly, from KSP landings. I always use the shadow.
$endgroup$
– dotancohen
Jul 8 at 11:22
4
$begingroup$
The cabin was very small, and the astronauts stood just behind the window to improve their downward view. There was nowhere else for the exit hatch to be placed.
$endgroup$
– Russell Borogove
Jul 8 at 13:00
6
$begingroup$
The low sun makes a lot of sense from the point of view of revealing surface relief during the descent. This meant the landing had to be made in the lunar morning or evening. Morning was always chosen because, in the event of any mishap, that gave them the maximum amount of daylight to resolve the issue.
$endgroup$
– Oscar Bravo
Jul 8 at 13:50
6
$begingroup$
@CGCampbell, it still makes sense to want to maximize the amount of daylight in case of a problem, even when the period from dawn to dusk lasts 348 hours. I'd rather have 324 hours to work on something if I'm stranded on another world, than just 24 hours. (Or rather, I'd prefer my useful working period to be determined by O2, and not daylight.)
$endgroup$
– Ghedipunk
Jul 8 at 17:42
12
12
$begingroup$
The third bullet point there is the key one - pilots would rather use shadows to judge altitude rather than blindly trusting doppler radar to indicate the descent rate and altitude of the LM. From what I've read, no landing was ever performed under autonomous control. Lovell intended to, but of course that never happened. It make sense for the ladder to be under the only windows on the ascent stage - ergo the ladder is on the dark side.
$endgroup$
– Snow
Jul 8 at 10:42
$begingroup$
The third bullet point there is the key one - pilots would rather use shadows to judge altitude rather than blindly trusting doppler radar to indicate the descent rate and altitude of the LM. From what I've read, no landing was ever performed under autonomous control. Lovell intended to, but of course that never happened. It make sense for the ladder to be under the only windows on the ascent stage - ergo the ladder is on the dark side.
$endgroup$
– Snow
Jul 8 at 10:42
7
7
$begingroup$
@Snow: That was my thinking exactly, from KSP landings. I always use the shadow.
$endgroup$
– dotancohen
Jul 8 at 11:22
$begingroup$
@Snow: That was my thinking exactly, from KSP landings. I always use the shadow.
$endgroup$
– dotancohen
Jul 8 at 11:22
4
4
$begingroup$
The cabin was very small, and the astronauts stood just behind the window to improve their downward view. There was nowhere else for the exit hatch to be placed.
$endgroup$
– Russell Borogove
Jul 8 at 13:00
$begingroup$
The cabin was very small, and the astronauts stood just behind the window to improve their downward view. There was nowhere else for the exit hatch to be placed.
$endgroup$
– Russell Borogove
Jul 8 at 13:00
6
6
$begingroup$
The low sun makes a lot of sense from the point of view of revealing surface relief during the descent. This meant the landing had to be made in the lunar morning or evening. Morning was always chosen because, in the event of any mishap, that gave them the maximum amount of daylight to resolve the issue.
$endgroup$
– Oscar Bravo
Jul 8 at 13:50
$begingroup$
The low sun makes a lot of sense from the point of view of revealing surface relief during the descent. This meant the landing had to be made in the lunar morning or evening. Morning was always chosen because, in the event of any mishap, that gave them the maximum amount of daylight to resolve the issue.
$endgroup$
– Oscar Bravo
Jul 8 at 13:50
6
6
$begingroup$
@CGCampbell, it still makes sense to want to maximize the amount of daylight in case of a problem, even when the period from dawn to dusk lasts 348 hours. I'd rather have 324 hours to work on something if I'm stranded on another world, than just 24 hours. (Or rather, I'd prefer my useful working period to be determined by O2, and not daylight.)
$endgroup$
– Ghedipunk
Jul 8 at 17:42
$begingroup$
@CGCampbell, it still makes sense to want to maximize the amount of daylight in case of a problem, even when the period from dawn to dusk lasts 348 hours. I'd rather have 324 hours to work on something if I'm stranded on another world, than just 24 hours. (Or rather, I'd prefer my useful working period to be determined by O2, and not daylight.)
$endgroup$
– Ghedipunk
Jul 8 at 17:42
|
show 10 more comments
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6
$begingroup$
Bonus: Whenever the Luna Rover is stationary the shadows of the sun-side wheels never fall on the far-side wheels. This is by design and not an astounding coincidence. [Somebody will probably now produce a photos falsifying this :-) , but that was the aim.]
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– Russell McMahon
Jul 8 at 6:53
3
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Bonus two: The shadow of the LEM is projected on both Aldrin and the lunar ground, why can't we see the ground?
$endgroup$
– qq jkztd
Jul 8 at 9:21
4
$begingroup$
@qqjkztd I think you lack some photographic background. It is not uncommon that the dynamic range of a camera make shadow dark enough to not be able to see details on it while white objects (the astronaut) light by a small reflector (here, the moon regolith) is bright enough to be seen (you can easily find reconstitution made with Lego on photographs' blogs and try to reproduce it yourself)
$endgroup$
– Manu H
Jul 8 at 9:27
4
$begingroup$
@qqjkztd This image shows the original plus a lightened version. I suspect that the black shadow has been further darkened - can't have original photos when they can be improved with editing. (I may be wrong). The 'black" is a very dark blue and is not quite homogeneous, but dies not have the variability I'd expect. [I often enough lighten up photos in this manner to check for editing]. || That said, the ground is horizontal and less liable to be highly illuminated by low angle reflected light.
$endgroup$
– Russell McMahon
Jul 8 at 10:43
8
$begingroup$
|| PhD thesis - Dynamic thermal modeling for moving objects on the Moon || p7 lower - ... During Apollo 14 the MET was used to transport instruments and equipment ... MET was designed to sustain minimal temperatures as low as 216 K. ... during surface operations one wheel fell below that threshold temperature only because it was shadowed by the other parts of the MET ... The Astronauts had to adopt to this unforeseen condition in order not to loose the MET. ... by positioning the MET Stack Overflow no shadow was casted on the wheels.
$endgroup$
– Russell McMahon
Jul 8 at 11:12