Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: PmbPhy on 22/06/2017 20:43:40
-
When Apollo 11 was close to the Moon the astronauts saw an object in the distance which was flashing. They said it was about 1 mile away. They came to believe that it was a panel from the stage where the LEM was extracted. However it doesn't seem likely to me. That panel was ejected almost three days prior to that. Suppose that it was left a residual speed of .5 mph after the panel was ejected. Two days later that panel would be 24 miles away. I can't see how they'd be able to see that from that distance. More accurately it was three days later and the panels were probably moving at 5 miles per hour making them 288 miles away.
Any thoughts?
-
A jagged piece of ice or stone from a meteor or comet that was slowly rotating, thus reflecting the Sun towards the module at different times? It's just a guess.
-
an object in the distance which was flashing. They said it was about 1 mile away.
Human binocular vision can't distinguish the distance of objects that are more than about 5 meters away. By moving your head backwards and forwards you may be able to double that, but Apollo spaceships were not renowned for their panoramic viewing windows.
You would need a radar to distinguish between an object at 30m or 1500m.
A jagged piece of ice or stone from a meteor or comet that was slowly rotating
I can believe the "slowly rotating" part.
But comets and meteors tend to be irregular in shape and rough in texture, giving a diffuse reflection, rather than a mirror-like (specular) reflection.
Apollo 11 traveled from Earth to Moon (and back). Comets and meteors typically travel at a relative velocity of around 10 km/second or higher relative to the Earth-Moon system. At these velocities, it would zip by without being seen at all.
-
A jagged piece of ice or stone from a meteor or comet that was slowly rotating, thus reflecting the Sun towards the module at different times? It's just a guess.
Ice can't reflect sunlight to that degree. At any rate it was flashing and I see no reason for a piece of ice to be non-symmetrical in their reflecting property to that extent. Have you ever seen a piece of ice reflect sun from a mile away? It appears as a constant white blotch.