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In magazine AS14/KK there are clear double LEM shadows present where only one should be. I can't find any evidence of double exposure. How did this happen? I've even found 2 shadows that overlap and have holes in them!

Apollo 14 shadow:
enter image description here
https://www.flickr.com/photos/projectapolloarchive/21692728531/in/album-72157659051610141/

Apollo 12 shadow:
Apollo 12 Shadow
https://www.flickr.com/photos/projectapolloarchive/21036341253/in/album-72157658982137872/

Original images at NASA (both magazines were B&W film)

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This is a double reflection of light between the LM window and the camera lens. There are no two shadows as if they are caused by two light sources. It's the same shadow captured twice in the photograph.

1) Moon craters inside and outside the outer shadow don't line up (especially obvious close to the upper orange line). They wouldn't be affected if the double shadow of the LM would be caused by two light sources. In fact, they show the same double images like the LM. I marked a few with same-colour lines in the image from Apollo 14: Apollo 12 images with marked craters

2) The position of the double shadow varies strongly as is visible in the video from Apollo 11 linked by @bruffy in the comments. Note that there is no double shadow in the third still were the camera is quite far away from the window as can be seen from the window frame that is rendered much sharper than in the middle image. In the first and second image the double shadow moves from left to right as the relative alignment between camera and window changes. Snapshots from https://www.youtube.com/watch?v=48lpMNf8nKc

3) Note that in the image from Apollo 12 there is no double shadow visible around the landing legs. If there were two light sources, these should be visible as well. In the photograph nothing is seen there because the bright light from the surface outshines the faint reflected light. Reflected light can only be seen in the pitch black area of the shadow cast by the LM.

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    $\begingroup$ I like this answer much better than mine! I've added a pointer to this one at the beginning of the other one. Very nice work!! This must be the right answer. $\endgroup$ – uhoh Jul 29 '19 at 16:32
  • $\begingroup$ Best answer yet, thanks @asdfex! However, wouldn't more features outside the LM like the rocks, other craters, thrusters and the horizon on the moon's surface be duplicated to some extent? Are there any diagrams that visually describe this effect? Thanks $\endgroup$ – Bruffy Jul 31 '19 at 18:44
  • $\begingroup$ @bruffy Everything does appear twice - but the reflection is so faint that you can't see it anywhere outside the pitch black shadow of the LM. The photographic film doesn't represent brightness correctly - the dynamic range is much larger than it seems. The shadow looks 1/4 as bright (according to uhoh) but in fact it is more like 1/20 or even less. In the bright areas you just can't see the difference. $\endgroup$ – asdfex Aug 1 '19 at 17:55
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update: After reading @asdfex's excellent answer I think it is probably the right answer. I'll leave this here because it addresses the double light source hypothesis quantitatively, but I recommend that one reads the other explanation as it's probably the right one!


I'm going to put forward a theory and support it with the positions of the Sun and Earth seen in the sky of the Apollo 12 and 14 landing sites.

Seen from the Moon, the Sun is about 0.5 degrees wide while the Earth is about 2.0 degrees wide. You would expect the Earth to be at least somewhat near the Sun in the sky because the launches were timed to provide good sunlight on the Moon.

What I see in both of these cropped bits from the original NASA images is a shorter, weaker shadow that's about 4x fuzzier than the longer, stronger shadow. That certainly seems consistent with a shadow of Earthshine being shorter than a shadow of Sunlight.

The notations for these frames (see annotations of the images below) suggest that both were taken soon after landing. According to my plots of data from JPL's Horizons using the landing dates and lunar coordinates of the landing sites, the Sun was quite low on the horizon while the Earth was already at an elevation of about 60 degrees above the horizon and obviously remains fairly constant.

Light from both the Sun and Earth come from nearly the same azimuth (not much surprise there) so the shadows from Sunlight and Earthshine should point in nearly the same direction, about 270 degrees azimuth.


Apollo 12 Landing site Ocean of Storms 3.01239°S 23.42157°W

Apollo 14 Landing site Fra Mauro 3.64530°S 17.47136°W

Here are azimuth and elevations of the Sun and Earth as seen from these Apollo landing sites. Time axis is hours since 00:00 on landing day. Sun is solid red, Earth is dashed blue.

and the Sun is rising. So the angle difference will depend on the exact time of the photograph.

I don't have time today to check those but the explanation seems consistent enough for now. I'll get back to the timestamps tomorrow.

Plotted using inelegant Python 3 script (updated) https://pastebin.com/n1M1iSKy

Apollo 12 and 14 positions of Sun and Earth in the sky

JPL Horizons web interface for Apollo landing

JPL Horizons web interface for Apollo landing


Cropped from NASA Apollo AS14-65-9211

above: Cropped from "Down-Sun with the dramatic washout." AS14-65-9211 at https://www.hq.nasa.gov/alsj/a14/AS14-65-9211HR.jpg found in Magazine 65 contains 14 pictures taken out the LM window after the landing..

below: Cropped from "LM shadow." AS12-48-7026 at https://www.hq.nasa.gov/alsj/a12/AS12-48-7026HR.jpg found in This Black and White magazine was used by Al Bean during EVA-2. The first 11 frames were taken from inside the LM before the first EVA..

Cropped from NASA Apollo AS12-48-7026

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    $\begingroup$ The sun is low in the lunar sky (the moon viewed from Earth is gibbous and the landing sites are always chosen to be near the sunny side of the terminator, for good landing shadows) so the Earth is quite high (a fat crescent). The only bright light source that is nearly aligned with the sun is the sun's reflection off the moon. $\endgroup$ – amI Jul 7 '19 at 7:07
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    $\begingroup$ @amI I still think it's the Earth, but this may take some time to resolve. Without a 3D terrain model it's impossible to do a 3D reconstruction of the LM shadows as seen from the camera, so it may be necessary to find a written source. $\endgroup$ – uhoh Jul 7 '19 at 7:44
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    $\begingroup$ I think you are right - the approx 45 degree difference in angles looks less due to fore-shortening. $\endgroup$ – amI Jul 7 '19 at 8:18
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    $\begingroup$ Hi, thanks for the comments. If you look at the album taken pre EVA 1 the overlap moves from frame to frame, L to R and up and down. Looking at the magazines 64/LL and 66/II you can see the sliver of the Earth high in the lunar sky with the LM 'nose' for reference. Looking at the 'selfie' shadows of Apollo 14 I cannot find any examples of overlapping shadows. So far I've found overlapping LM shadows in all missions except for 17 and 13 of course. Strange $\endgroup$ – Bruffy Jul 8 '19 at 1:34
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    $\begingroup$ @Bruffy a substantial amount of overlap moving "from frame to frame, L to R and up and down" wouldn't be consistent with two relatively fixed sources of light, hmm... I'll try to take a look today. Thanks! $\endgroup$ – uhoh Jul 8 '19 at 3:24
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The conclusion of the analysis at https://www.aulis.com/double_shadow.htm is that reflexions between the panels of the forward windows and/or the camera optics cannot produce the observed pattern. Therefore, it actually is a double shadow or an artifact of a some sort of a front projection apparatus.

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    $\begingroup$ Moon-hoaxer nonsense. " this interpretation would mean that the photographs in question were not taken on the Moon. " $\endgroup$ – Organic Marble Jan 4 at 22:40
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    $\begingroup$ IMHO the overall conclusion of the article from your link is not correct. The case number 6 (Deformed inner window) actually makes sense and fits the situation best (the article author even admits the shadows are relatively well represented). @asdfex's answer below describes very well why the double shadow for horizon and some craters aren't visible: because it's casted on the very bright portion of the image. $\endgroup$ – LeoS Jan 4 at 23:34

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