In June and July of 2003 NASA launched two robot rovers with goal of gathering information about the little understood planet Mars. Previous expeditions offered us a lot of details, but they have been few and fleeting visits and not nearly enough information has been accumulated yet.
The rovers, Spirit and Chance were expected to last 90 Martian days at best, but after greater than 1000 Martian days on, they were still going strong.
At only 180 kg each they brought batteries, communication tools, and photovoltaic panels and used expert systems that enabled them to refuse to do what their controllers told them, if they really felt an activity would be dangerous. They lasted greater than 10 times the period initially intended and tripping across a range of greater than 10 miles of the Martian surface.
The first one to make it to the surface of Mars was the rover nicknamed Spirit. Spirit landed on Mars January 4th, 2004 in a crater 10km from the target. Spirit made several vital discoveries. From its start in the crater, it has actually found many rocks of volcanic origin and also the activity of subsurface water on these rocks. Spirit found patches of soil with a high salt material that has the tendency to be caused by the previous visibility of water. It found additionally one especially fascinating rock, nicknamed Humphrey, a volcanic-like rock formed perhaps by lava. It had actually vibrantly coloured, mineralised parts inside, that would probably be frommed from water passing over it, before or sometime after the rock was developed. This finding dispelled uncertainties from lots of researchers whether water existed or otherwise on Mars a long time in the past.
Spirit not only helped us comprehend a lot more geological and physical elements of Mars – Spirit took the first picture of Earth from the surface of another planet. Spirit also took night-time pictures of the of the moons as well as Mercury and was fortunate to capture a lunar eclipse of the Mars’ moon Phobos.
Chance, the second rover to make it to the surface of Mars, landed 21 days after Spirit on January 25th, 2004 on the other side of the red planet. Chance evaded rocks in craters probably caused by sulphite abundant sands from vaporized lakes compressed and forced to the surface and then eroded by wind as well as water. Again proof that water once existed on Mars.
The two rovers have sent back many images of the Martian surface in both grey-scale and colour. These are both lovely and scenic images. Equipped with a geological package as well as motorised rock tools, they were able to look below the surface to uncover even more than thought possible.
All these new discoveries have boosted our space exploration expertise while at the same time enhancing the our knowledge Mars. However the questions still remain. Why did the water vanish? Did life once exist on Mars? Could human beings survive on the planet?