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photogenic coincidence?


michel123456

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from here

Why would the shadow of a
space shuttle
launch plume point toward the Moon?


sts98plume_nasa_1111.jpg

Followed by the explanation:

Explanation: Why would the shadow of a space shuttle launch plume point toward the Moon? In early 2001 during a launch of Atlantis, the Sun, Earth, Moon, and rocket were all properly aligned for this photogenic coincidence. First, for the space shuttle's plume to cast a long shadow, the time of day must be either near sunrise or sunset. Only then will the shadow be its longest and extend all the way to the horizon. Finally, during a Full Moon, the Sun and Moon are on opposite sides of the sky. Just after sunset, for example, the Sun is slightly below the horizon, and, in the other direction, the Moon is slightly above the horizon. Therefore, as Atlantis blasted off, just after sunset, its shadow projected away from the Sun toward the opposite horizon, where the Full Moon just happened to be.

Well that is all correct, except that the 2 terms " photogenic coincidence" and "the full moon happened to be" look misleading to me.

 

The full moon is produced by the reflection of the light of the sun. It means that any object in the sky at that same instant at any random place (an airplane, a balloon, a bird) would produce a shadow pointing to the Moon. So the Moon didn't "happen to be there" in coincidence with the shadow. The shadow was "obliged" to point to the full Moon.

 

Of course the shuttle was not "obliged" to take off at full Moon, but as I read the explanation it was somehow unclear. In any case there is no "photogenic coincidence".

 

Right or wrong?



the configuration is the following


sunearthmoon.jpg



It is a law of perspective: all the parallel lines join to the same vanishing point.

All rays of light in the sky join at the same point. That is the point where the Moon is lighted.

 

I think.

Edited by michel123456
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yes, but you also get the light of the full moon in the same time. Your arrow can also go to the moon to earth. I can agree that the rays received on earth by the moon, are anterior from sun at this 'present emitting'



"The smoke shadow" thus receives two lights



We could almost compare it to the delayed choice double-slit experiment... almost.

Edited by Arnaud Antoine ANDRIEU
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It's a coincidence in the sense that shadows don't always point toward the moon and they didn't set it up intentionally to create a situation where it would.

 

It's not a coincidence in that there are specific, non-arbitrary reasons that this event happened, but very few things qualify as being coincidental if you trace the causes of them far enough.

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