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To: Robert A. Cook, PE

Uh.. well simply no. The resolution of a telescope is angular, not spatial. Spatial can be calculated by the distance to the object, which the moon is LOTS farther than the earth from that orbit.

Second, the Hubble primary mirror error, a mistake in the conic constant of the surface due to a cap on the metering rod used for setting up the null test, was corrected by first using phase retrieval systems to validate the error then fixed using a lens system.

The resolution of the telescope, since it is now diffraction limited, is found by alpha = 2.44 * lamda / D, D being the diameter of the entrance pupil (2.4 meters), lamda being ~.5 micron. Alpha, therefore, is .5 micro Radian. The angular subtense of a 1 meter object sitting on the moon (385000 km) as viewed from a 569km orbit is 2.6 nano Radians. To resolve a 1 meter object, the primary mirror would have to be 2.44*.5E-6/2.6e-9, or 469 meters. That don't fit in a 4 meter payload ferring.


31 posted on 10/19/2005 11:24:37 PM PDT by Third Order
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To: Third Order

Easy for you to say.


33 posted on 10/19/2005 11:45:06 PM PDT by razorback-bert
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To: Third Order

OK - Good point: And even an spatial resolution (385,000 km vice 569 km) would reduce resolution by a larger factor.

I appreciate the correction.


37 posted on 10/20/2005 4:14:54 AM PDT by Robert A Cook PE (-I contribute to FR monthly, but ABBCNNBCBS supports Hillary's Secular Sexual Socialism every day.)
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