While you may be aware of NASA's historic Curiosity mission (and the current problems it's facing), you might not have heard of the Mars Reconnaissance Orbiter, or MRO. The craft has been in orbit around the Red Planet since 2006 and its latest research, a 3D scan of a huge underground channel system, has provided researchers with an insight into the planet's recent hydrologic activity.
The scans reveal a channel system created during a catastrophic flooding event that is thought to have taken place within the last 500 million years, a period of the Red Planet's history that has previously been considered cold and dry. The new data on the channels will help scientists determine whether the flooding may have played a part in climate change events.
The 620 mile (1,000 km) long Marte Vallis channel system is located along the planet's equator, in a set of plains known as the Elysium Planitia. The area is the youngest volcanic region on Mars, with much of the plains' geological history, including the source of the channels, hidden from view beneath volcanic debris.
The team used the MRO's Shallow Radar (SHARAD) to examine the underground channels, building a 3D model based on its readings. What they found was a system that was similar to some of the more ancient channel systems on Mars, including the Chryse basin, a feature which is thought may also have been formed by large volumes of water.
The scans suggest that the Marte Vallis channels were formed in two stages, with the water carving out a number of smaller channels before the deeper and wider main channels were formed. The water itself is thought to have accumulated in an underground reservoir before being released by volcanic or tectonic activity.
The size of the flooding is comparable to the ancient mega flood that created the Channelled Scablands of the Pacific Northwest United States. Gareth Morgan, a geologist at the National Air and Space Museum's Center for Earth and Planetary Studies in Washington, said “Our findings show the scale of erosion that created the channels previously was underestimated and the channel depth was at least twice that of previous approximations.”