Widespread deposits of carbonate rock are buried a few miles beneath the surface, according to new research. Small amounts of this mineral have been detected on Mars before. But if they are abundant it means the greenhouse gas could have helped make it a much wetter and warmer place hundreds of millions of years ago. Read more
NASA's High Resolution Imaging Science Experiment (HiRISE) camera orbiting Mars spotted this 'bullseye' crater which has left scientists baffled as to how it was created. See more
Researchers have identified rocks that they say could contain the fossilised remains of life on early Mars. The team made their discovery in the ancient rocks of Nili Fossae. Their work has revealed that this trench on the dark side of Mars is a "dead ringer" for a region in Australia where some of the earliest evidence of life on Earth has been buried and preserved in mineral form. Read more
After the Mars Global Surveyor (MGS) settled into orbit around the red planet in 1997, a magnetometer on board began sending back measurements that have puzzled planetary scientists ever since. A section of the martian crust appeared to consist of long 'stripes' of iron-bearing minerals permanently magnetised with alternating orientations. Clearly, an ancient dynamo imprinted its field in the rock during the planet's early history. But why the stripes? Now, Ken Sprenke of the University of Idaho in Moscow, Idaho, has provided a tantalizing theory to explain these stripes: they were created by ancient hotspots beneath the crust. The hotspots would exhume material from the interior that would then 'freeze' with the magnetic field holding sway at the time. Read more
US scientists have found further evidence that huge seas existed long ago on Mars. A geological mapping project found sedimentary deposits in a region called Hellas Planitia which suggest a large sea once stood there. The 2,000 km-wide, 8km-deep Hellas basin is a giant impact crater - the largest such structure on Mars. Read more
Deposits of volcanic ash colour this view of the Meridiani Planum, as seen by the Mars Express High Resolution Stereo Camera. They also give clues to the prevailing wind direction in this region of Mars. Meridiani Planum, a plain at the northern edge of the southern highlands of Mars, is half way between the volcanic Tharsis Region to the west and the low-lying Hellas Planitia impact basin to the south-east. Through a telescope, Meridiani Planum is a striking, dark feature, close to the martian equator.
Flowing lava can carve or build paths very much like the riverbeds and canyons etched by water, and this probably explains at least one of the meandering channels on the surface of Mars. These results were presented on March 4, 2010 at the 41st Lunar and Planetary Science Conference by Jacob Bleacher at NASAs Goddard Space Flight Centre, Greenbelt, Md. Whether channels on Mars were formed by water or by lava has been debated for years, and the outcome is thought to influence the likelihood of finding life there. Read more
Future Martian explorers should find it easier to locate minerals deposits on Mars thanks to a team of Australian researchers. The study, which appears in the journal Planetary and Space Science, could also help in the search for life on the red planet. Michael West of the Australian National University and Dr Jonathan Clarke of University of New South Wales say while there is mineral wealth on Mars, it won't be easy to access. Read more
Near the center of a Martian crater about the size of Connecticut, hundreds of exposed rock layers form a mound as tall as the Rockies and reveal a record of major environmental changes on Mars billions of years ago. The history told by this tall parfait of layers inside Gale Crater matches what has been proposed in recent years as the dominant planet-wide pattern for early Mars, according to a new report by geologists using instruments on NASA's Mars Reconnaissance Orbiter. Read more
Part of the Sirenum Fossae region in the Southern Highlands of Mars.
The Mars Express High Resolution Stereo Camera has imaged craters both young and old in this view of the Southern Highlands of Mars. Part of the Sirenum Fossae region in the Southern Highlands, the area in this image is centred at about 28°S / 185°E. The image captures an area to the north of the Magelhaens Crater. It extends some 230 km by 127 km and covers about 29 450 sq km, roughly the size of Belgium. The image resolution is approximately 29 metres per pixel.