Mars has a case of the munchies. That is, the red planet is spotted with vegetation with some sort of life feasting on the foliage. So says Arthur Clarke, the noted sci-fi writer and space visionary, making the claim during a recent conference on the space elevator. Clarke was keynote speaker at the 2nd annual international conference on the space elevator, held in Santa Fe, New Mexico. Sir Arthur beamed into the gathering by satellite link on September 13.