Quote:
Originally Posted by shybastid
Thanks.. you guys..Hubble question answered.
Ummmm?? Can the NEW satellites from other countries record current photo's of our leftover debris?
If google can record every inch of Earth with THEIR satellites,we should get be able to close ups of the moon,right? Or am I being redundit? Sorry if I am.
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The moon is too far away to resolve anything as small as a flag unless you put a satellite in orbit around it at a similar distance as the ones currently used for Earth mapping etc.
Some of the best resolution mapping is actually not optical but of different wavelengths.
Here's the maths..
The moon is about 221000 miles away and lets say the flag is 6 foot high.
To optically resolve the flag we would need to do some trigonometry for the angle of resolution.
Imagine a triangle with the long bottom side the 221000 miles (1,166,880,000 feet) and the vertical side is 6 feet for the flag at the moon.
We know the opposite and the adjacent lengths so we use tangent.
Tan 6/1166880000 = 5.14x10 to the power of -9.
Or .0000000051 is probably simpler to see.
That's .0000000051 radians, convert to degrees and we get 0.000000295 degrees.
So we would need a telescope capable of resolving 0.000000295 degrees of arc...or .001060596 arc seconds.
Just over a thousandth of an arc second.
To those who don't understand it's probably best to take that figure and put it to a size for a telescope..
To do that we need to use Dawes Limit-
http://en.wikipedia.org/wiki/Dawes_limit
The telescopes mirror diameter can be calculated from the formula shown there- D(in inches)=4.56/arc seconds
So 4.56/0.001060596= z0mgwtfbbqcornflakes
4300 inches in diameter.
That's 358 feet across.
Let me know when NASA build one
EDIT- It's worth noting that 221000 miles is the figure for closest approach, the moon is actually as far away as a quarter of a million miles at it's furthest.