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Old 01-07-2017, 01:57 AM
dtilque dtilque is online now
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Originally Posted by markn+ View Post
The angular diameter of Mars as seen from Earth varies quite a bit depending on the position of the planets in their orbits, from about 3.5 arc seconds to over 25. So Earth's angular diameter as seen from Mars should vary in the same way, except Earth would be about twice the diameter, varying between 7 and 50 arc seconds.
Earth's albedo (fraction of light reflected back to space) is about twice Mars', so it's going to be brighter for that was well. I'd say that Earth as seen from Mars will be more like Venus from Earth, than Mars from Earth. Especially so since it'll go through phases like Venus does.

Originally Posted by Francis Vaughan View Post
Jupiter's disk however will remain unresolved. It will still be a point.
Jupiter is not quite a point to the naked eye. Stars are point sources and because of that, they twinkle due to atmospheric irregularities. Planets don't twinkle as much as stars do, because they do show just a bit of disk. This effect should be more pronounced when seeing Jupiter at Mars, but you still won't be able to see any detail on Jupiter.