There are several magnificent canyons right here on Earth with the Grand Canyon in Arizona being one of the most well known. The “greatest” canyon on Earth is Yarlung Tsangpo which is located in Tibet and China. The deepest ravine on our planet is the Mariana Trench in the Pacific Ocean which goes down approximately 36,000 feet underwater. And while these are all very impressive, the largest canyon in our entire Solar System is actually located on Mars.
The Valles Marineris stretches out almost a quarter of Mars’ circumference around its equator at over 2,500 miles long. To put this into better perspective, it is almost ten times longer than the Grand Canyon and three times deeper. In addition to being the biggest canyon in our Solar System, it is also one of the most mysterious as scientists are unsure as to how it was formed.
It is highly unlikely that the canyon was formed by billions of years of rushing water because Mars is so dry and hot. On the other hand, researchers from the European Space Agency (ESA) have stated that there is evidence that some of the canyon’s channels could have been made deeper by flowing water on the planet hundreds of millions of years ago.
According to the ESA, most of the canyon was more than likely opened up billions of years ago when a group of volcanoes called the Tharsis Montes region first formed. That region measures about 4,000 kilometers across (almost 2,500 miles), 10 kilometers in height (6.2 miles) and has 12 large volcanoes including Olympus Mons which is the largest in the Solar System. When the magma bubbled up underneath the volcanoes, the crust of the planet may have stretched, causing the ground to collapse which ultimately created the large canyon known as Valles Marineris. Additional evidence indicates that magma flows, landslides, and ancient rivers more than likely had some effect on the development of the canyon although how much is unclear.
A high-resolution camera on the Mars Reconnaissance Orbiter called HiRISE has been taking photographs of the Red Planet’s features since 2006 which includes some close-up images of the gigantic canyon. The pictures can be seen here as well as on the HiRISE website.
Experts still have a lot more work to do in order to conclude for sure how the canyon was formed and the high-resolution photos will certainly help with their research.