Massive Mars rock from outer space could fetch up to $4M at prestigious Sotheby's auction

The largest-known piece of Mars ever found on Earth is going up for auction on Wednesday and could fetch as much as $4 million because of the rareness of an extraterrestrial item.Sotheby’s auction house is opening the bidding on a meteorite that it calls "an incredibly rare discovery," at $1.6 million.According to the auction site, bidders are bidding on the largest piece of Mars on Earth, which was ejected from the Martian surface by a massive asteroid strike.After the strike, the rock traveled 140 million miles through space and hurtled through the Earth’s atmosphere before crashing in the S