Are you a Martian?
Are we all Martians? According to many planetary scientists, it's conceivable that all life on Earth is descended from organisms that originated on Mars and were carried here aboard meteorites. If that's the case, an instrument being developed by researchers at MIT and Harvard could provide the clinching evidence. In order to detect signs of past or present life on Mars — if it is in fact true that we're related — then a promising strategy would be to search for DNA or RNA, and specifically for particular sequences of these molecules that are nearly universal in all forms of terrestrial life. That's the strategy being pursued by MIT research scientist Christopher Carr and postdoctoral associate Clarissa Lui, working with Maria Zuber, head of MIT's Department of Earth, Atmospheric and Planetary Sciences (EAPS), and Gary Ruvkun, a molecular biologist at the Massachusetts General Hospital and Harvard University, who came...