Putative Martian Microbes Called Microscopy Artifacts

Ever since they made their public debut 15 months ago, the squiggly little objects that mightor might notbe microscopic fossils in a meteorite from Mars have been at the center of a heated debate. Most scientists have focused on arcane arguments about mineral isotopic compositions and formation temperatures (Science, 4 April, p. 30), but for many, the proposed microfossils provoked a more visceral reactionthey simply look lifelike. Looks can be deceptive, however, and a group of three meteoriticists now argues that there's nothing lifelike about the martian bugs. Rather, they're simply a trick of the eye abetted by the peculiarities of the powerful microscopes used to image them.