Author Topic: Hot new "anomaly": Missing shadow in 5903  (Read 6698 times)

Offline JayUtah

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Re: Hot new "anomaly": Missing shadow in 5903
« Reply #15 on: January 20, 2015, 09:28:37 PM »
Both the PLSS and the RCU can flop around a lot.  When we first rigged up the suits, I was surprised.  So yes, we know the astronauts had to lean in order to accommodate the eccentric position of the PLSS.

There is also possibly a physiological explanation.  One of the effects of diminished gravity, as the crews reported, is diminished balance.  Equilibrium, it turns out, is fairly highly attuned to rotation rates evolved in Earth gravity.  And you don't topple fast enough in lunar gravity to trigger an uprighting reflex.  This means "upright" on the Moon is a broader cone of roughly vertical angles.
"Facts are stubborn things." --John Adams

Offline ka9q

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Re: Hot new "anomaly": Missing shadow in 5903
« Reply #16 on: January 21, 2015, 12:06:27 AM »
Interesting. I can see how low gravity might do that, but you still have to keep your c.g. over and between your feet or you'll fall over. Every lunar astronaut exhibits a noticeable forward lean because of his backward shift in c.g., but I don't think I've noticed consistently rotated pictures from anybody but Armstrong. I wonder what would explain that? As far as I know, there weren't any significant changes to the PLSS until Apollo 15, though some extra shades were added to the LEVAs.


Offline BertieSlack

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Re: Hot new "anomaly": Missing shadow in 5903
« Reply #17 on: January 24, 2015, 02:33:32 AM »
I think you're right.  Look at how the shadow of his left leg diverges from the shadow of the strut.  They only intersect at his foot, and I think his left foot is actually in the shadow.  The thing to remember is that, although leaning slightly to his left, Armstrong is basically standing upright, whereas the strut is at a significant angle from vertical.

You can see that really well in this still from the 16mm DAC film camera in Buzz's window:

http://www.hq.nasa.gov/alsj/a11/a11ArmstrongTakes5903.jpg

With the reflection, the visor acts essentially as a super-wide-angle lens and perspective convergence of receding objects is exaggerated. This makes the strut shadow appear to be more behind Neil than it really is. I think the fact that Neil is not facing directly up-sun adds to this illusion - his shadow and the strut shadow are to some extent running across the frame.

Offline BertieSlack

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Re: Hot new "anomaly": Missing shadow in 5903
« Reply #18 on: May 28, 2016, 03:22:38 PM »
For anyone considering looking at the DAC images of when Neil took this picture, don't bother. It doesn't go down far enough. I watched the TV transmission and I don't think it showed this moment. I'm pessimistic about it revealing anything of value, anyway.

Watch the 16mm DAC footage of Neil collecting the contingency sample. He stands in the shadow of the landing leg but doesn't block it. The shadow falls on the outside of his leg - and in the visor reflection when he took the photo of Buzz we wouldn't be able to see that because of the angle. The only part of the shadow we'd be able to see on Neil would fall on top his boot. Here's the footage -
- watch right from the beginning, and then freeze at 00:4.