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Comment by artmageddon | Hacker News Reader

Silly question, but why is it that we can't fly a satellite into the orbit of Mars? What is it about the space 300 miles up from Earth that differs from Mars? (unless we also want to discuss geosynchronous orbit)

Edit: I should have written "launch" a satellite into Orbit from Earth to Mars

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Orbit isn't about going up - it's about going sideways so fast that the planet curves away just as fast as you fall towards it. While you can use the atmosphere to lift yourself up to a certain extent, it doesn't help you achieve orbit. The 100km boundary for space on Earth isn't picked as just a clean number - it's the altitude at which a plane would have to fly at orbital speeds to generate the required lift, and if you're going orbital speeds you don't need lift.

I know this doesn't exactly answer your question, but it might help to frame it better.

I probably should have phrased it better, actually. I understand the concept that the satellites are falling along a path in orbit that causes them to "miss" the planet as you describe. I misunderstood the parent's phrasing use of flying, which implies the presence of an atmosphere, as opposed to just "putting" a satellite into Mars orbit(by way of launching a rocket with the desired payload or whatever).

Actually we currently have 3 satellites orbiting Mars:

http://en.m.wikipedia.org/wiki/Category:Artificial_satellite...

"Same reason we can't fly satellites into orbit [of Earth]"

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