A recent study suggests that not only was Mars a transiently watery world in its past, but that it also had an atmosphere — which today is only 1% as dense as Earth’s — that was 20 times denser.
(Image from NASA/JPL)
Not just an unmanned mission to Mars, but a mission that prioritizes the search for life and the goal to bring Martian materials back to Earth. Certainly the possibility of finding life is there, but hopefully rovers could select samples that would contain evidence of past life.
(Image from Astrobiology Magazine)
Asteroid impact craters on Earth, even those from impacts that occurred tens of millions of years ago, hide creches of life beneath their surfaces, due to the protection they provide from the seasonal cycle and from more catastrophic changes like ice ages. If Mars (or other planets) are hiding life, drilling below their craters may reveal life.
(Image from the NSF)
Scientists had previously noted strange dark areas on the Martian surface; a recent study suggests that these areas are actually regions of glass, forged courtesy of past volcanoes. On Earth, such phenomena do exist, but only after being weathered by water, which may be further evidence that water has existed on the red planet.
(Image from NASA)
These periodic bedrock ridges are unheard of on Earth and reveal some interesting information about Martian weather and tectonics — and perhaps something even more exiting: Scientists hope that the weathered rock will provide a visible geological history of Mars and shed some light onto what the red planet was once like.
(Image from Science Daily)