Free Republic
Browse · Search
News/Activism
Topics · Post Article

To: Third Order
Nah: Hubble has the same 1-2 foot resolution that the CIA/NSA satellites have. Moon has no atmosphere or dust to interfere either.

Hubble is same technology, made by the same lab on the same machines that are making the spy satellite camera (mirrors, mounts, foundations, controls, sensors, radios, drives, anti-motion (random satellite movement) controls/motion-following satellite (image tracking) controls and motors.

Problem with Hubble was the calibration of the grinding machinery (fundamentally) that incorrectly spaced and sized the mirror surface. Fortunately, it was a known error that they figured out how to re-correct with new hardware/software that could be loaded into the Hubble while in space.

23 posted on 10/19/2005 9:55:16 PM PDT by Robert A Cook PE (-I contribute to FR monthly, but ABBCNNBCBS supports Hillary's Secular Sexual Socialism every day.)
[ Post Reply | Private Reply | To 16 | View Replies ]


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
[ Post Reply | Private Reply | To 23 | View Replies ]

Free Republic
Browse · Search
News/Activism
Topics · Post Article


FreeRepublic, LLC, PO BOX 9771, FRESNO, CA 93794
FreeRepublic.com is powered by software copyright 2000-2008 John Robinson