Tom Shain holds a computer chip with about 35,000 signatures of visitors to the Mars Exploration Rovers at the Jet Propulsion Laboratory.

Tom Shain, the MER ATLO logistics manager, holds a computer chip with about 35,000 laser-engraved signatures of visitors to the Mars Exploration Rovers at the Jet Propulsion Laboratory. He and Jim Lloyd, also with the program, will place the chip on the second rover to be launched to Mars (MER-1/MER-B); the first rover already has one. The signatures include those of senators, artists, and John Glenn. The identical Mars rovers are scheduled to launch June 5 and June 25 from Cape Canaveral Air Force Station.