Comment Re:But the cultural impact... (Score 4, Interesting) 257
You make a very interesting point here, one that sent me running to look up some numbers and find a calculator. My fast crappy math seems to suggest that we could very plausibly see the moon from Mars with a decent camera.
When the rovers were launched, Mars was about 78 million km from Earth. The average distance from Earth to the moon is roughly 400000 km. So assuming the angles are right, there would be a maximum angular separation of about s/r = 0.005 radians or 0.3 degrees - more than enough to distinguish with the naked eye. The moon is fairly large; its diameter is about 3/4 that of Mercury. Although it is not as brightly illuminated due to greater distance from the sun, my intuition is that it ought to be visible to the naked eye.
I don't know if the Spirit or the Opportunity cameras are up to it, or if the orbital configurations are so convenient right now, but a photo of the Earth and moon like that you suggest seems entirely plausible.
When the rovers were launched, Mars was about 78 million km from Earth. The average distance from Earth to the moon is roughly 400000 km. So assuming the angles are right, there would be a maximum angular separation of about s/r = 0.005 radians or 0.3 degrees - more than enough to distinguish with the naked eye. The moon is fairly large; its diameter is about 3/4 that of Mercury. Although it is not as brightly illuminated due to greater distance from the sun, my intuition is that it ought to be visible to the naked eye.
I don't know if the Spirit or the Opportunity cameras are up to it, or if the orbital configurations are so convenient right now, but a photo of the Earth and moon like that you suggest seems entirely plausible.
