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Why Mars May Be Difficult

Posted by timothy on from the or-rather-is dept.

An anonymous reader writes with a link to this "dramatic article leading up to the three Mars probes for December/January at NASA's JPL (also hosted at Ames) on Mars risks: Two out of three missions to the red planet have failed. After 300 million miles of deep space, 'One colleague describes the entry, descent and landing as six minutes of terror,' says Dr. Firouz Naderi, manager of the Mars Program Office. Descending at 1,000 miles per hour, with only 100 seconds left at the altitude that a commercial airliner typically flies -- things need to happen in a hurry. Doesn't mention solar flares, electronics shielding, signal snags or budget tightening. The previous account listed the top 10 reasons Mars was hard in 1976."

2 of 57 comments (clear)

  1. Maybe it's our solutions? by blankinthefill · · Score: 5, Interesting

    After reading that, and seeing conceptual pictures of how these "landings" occur, I think that what makes Mars "hard" is our solutions to landing problems, and maybe even transportation. I don't know what we could do about transportation, but the landings are obviously way to stressful for delicate equipment. There has to be a better way to do it, because a landing like the one described would destroy almost anything! I don't think, therefore, that Mars itself is hard. I think it's how we access Mars that's "hard"!

    1. Re:Maybe it's our solutions? by matzim · · Score: 5, Insightful
      After reading that, and seeing conceptual pictures of how these "landings" occur, I think that what makes Mars "hard" is our solutions to landing problems, and maybe even transportation. I don't know what we could do about transportation, but the landings are obviously way to [sic] stressful for delicate equipment.

      Consider the following:

      • These probes are traveling to Mars at (least) 19,300 km/hr.
      • It needs to travel that fast to get out of Earth's gravitational field and orbit.
      • The only economically feasible way to slow down a craft going that speed is aerobraking.
      • You need to be in a planet's atmosphere to aerobrake.
      • Mars' atmosphere is (at most) a few hundred kilometers thick.
      • Anything going that fast isn't going to have a long time to slow down.

      Thus the problem is unavoidable-- you must go from 19,300 km/hr to 0 km/hr in a matter of minutes. If you can think of a method to do that that's less "stressful" than NASA's, we're all eager to hear it.