Phoenix Mars Lander officially dead NASA has confirmed that its Phoenix Mars Lander has not survived the harsh Red Planet arctic winter, and appears to have suffered serious ice damage to its solar panels. The agency has been attempting to contact the lander since January, in the slim hope it may have supported the weight of up to 30cm of accumulated carbon …
Diameter of a golf ball: 42.67 mm
Minimum altitude of a spy satellite: 100 km
Wavelength of visible light: 400 nm - 800 nm
So a telescope with a one metre objective might be able to see a golf ball from orbit (ignoring many other possible relevant factors).
Hubble has a 2.4 m mirror. If you remember, there was a problem with it being focused incorrectly. I did wonder at the time whether it had been accidentally focused for spying on the Earth instead of for astronomy ...
Putting a large telescope in a low orbit round Mars is quite another matter ...
Military photo reconnaissance satellites originally used extremely high resolution stereo film, which was ejected back to earth and recovered by special teams. That film was taken by very large cameras, and the satellite was pretty much built around the camera. When they moved to electronic image capturing, the satellites became significantly larger, again, built around the idea of a suitable sized focal system.
For a better example, the space telescope Hubble is essentially a civillian version of the early 70s Keyhole satellites, which are estimated to have a resolution of around 6" from a 2.4m mirror. Not exactly something that can be easily shipped to mars, and rather lacking in other significant scientific instrumentation.
Military recon sats have high resolution cameras with the capabilities that you have read about, but in those cases the cameras are so large that they generally have to build the satellite around the camera. Not something that is possible for a general-purpose science satellite with a limited payload mass (where every gram has to be justified - trust me, I've been involved in that side of things).
Also the military don't really want their cameras being used in by civies. Can't think why :-)
You are the weakest link - goodbye.
Yes, yes. Well done Timmy. Off to the top of the class with you. And after I've eaten my apple, perhaps you can explain to the boys and girls why, when discussing chemical compounds of Martian (or any other extra-terrestrial) origin, it is more appropriate to use their formulaic name (CaCO3, calcium carbonate in this example) rather than slightly vague terms such as chalk, limestone, aragonite, calcite etc. etc.
Research is for pedants dontcha know?
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