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To: MrNeutron1962
"I don't think the Hubble can resolve objects that small at that distance"

Of course they can. Spy satilites can read a license plate from a geosyncrous orbit 23K miles above the earth, through the earth's atmosphere.

The moon is in an elliptical orbit ranging from 220,000 to about 252,000 miles from Earth. Only ten times the distance, and you don't have to contend with our atmosphere.
47 posted on 11/07/2002 3:23:57 PM PST by babygene
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To: babygene
The moon is in an elliptical orbit ranging from 220,000 to about 252,000 miles from Earth. Only ten times the distance, and you don't have to contend with our atmosphere.

You are WAY off here. The size of a telescope's mirror limits it's resolution. I copied this off this webiste:

    The wavelength of visible light is around 550x10^-9m.

    The diameter of Hubble's mirror is 2.4m.

    Highest ever physically possible resolution = 1.4 x 550 x 10^-9 /2.4 m = 3.2 x 10^-7 radians

    At a distance of 350,000km this works out as about 124 metres.

Ever use a slide rule?

Yep, many "moons" ago. Ever do orbital mechanics?

49 posted on 11/07/2002 3:35:51 PM PST by TomB
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To: babygene
"I don't think the Hubble can resolve objects that small at that distance"

This is correct.

Of course they can. Spy satilites can read a license plate from a geosyncrous orbit 23K miles above the earth, through the earth's atmosphere.

Spy Satellites are not geosynchronous -- they orbit around 400 miles up.

The highest resolution commercially available is one meter. If the military can read license plates, they're not doing it from 23k miles away.

52 posted on 11/07/2002 3:49:55 PM PST by forsnax5
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To: babygene
Spy satilites can read a license plate from a geosyncrous orbit 23K miles above the earth

Spysats are in lower orbits, precisely because they need to maximize ground imaging resolution. 23K miles in the geosynchronous orbit used for comsats that "hover" above a specific point on the equator.

61 posted on 11/07/2002 5:25:00 PM PST by steve-b
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