THERE was great excitement last week when news leaked out that a spacecraft
has seen signs that water might have recently flowed on Mars’s surface. But
experts are puzzled by how water could be liquid in the frigid Martian climate
and warn that concrete proof will be hard to come by.
“If these results prove true, that there is water on Mars near the surface,
it has profound implications for the possibility of life on Mars,” NASA’s
associate administrator for space science Ed Weiler told a press conference in
Washington DC last week. “Just about any place biologists find liquid…
