Mercury is shrinking? 'Great Valley' discovered on the planet points at evidence, says NASA! - See pic

Mercury’s “great valley” (dark blue) is revealed in this high-resolution digital elevation model merged with an image mosaic. (Image courtesy: NASA/JHUAPL/Carnegie Institution of Washington/DLR/Smithsonian Institution)

Washington: Mercury, the small planet closest to the sun, is now on scientists' radar after they discovered a 'great valley' in its southern hemisphere.

This latest discovery simply adds fuel to the fact that the planet is gradually shrinking, after the team of scientists at NASA, made use of stereo images from the space agency's MESSENGER spacecraft to create a high-resolution topo map that revealed the broad valley.

About 250 miles (400 kilometers) wide and 2 miles (3 kilometers) deep, Mercury’s great valley is smaller than Mars’ Valles Marineris, but larger than North America’s Grand Canyon and wider and deeper than the Great Rift Valley in East Africa, NASA reported.

"Unlike Earth's Great Rift Valley, Mercury's great valley is not caused by the pulling apart of lithospheric plates due to plate tectonics; it is the result of the global contraction of a shrinking one-plate planet," said lead author of the study Tom Watters, senior scientist at the Smithsonian National Air and Space Museum in Washington DC.

Mercury's great valley is bound by two large fault scarps cliff-like landforms that resemble stair steps. The scarps formed as Mercury's interior cooled and the planet's shrinking was accommodated by the crustal rocks being pushed together, thrusting them upward along fault lines, the study said.

NASA's MErcury Surface, Space ENvironment, Geochemistry and Ranging (MESSENGER) mission was launched on August 3, 2004 to understand Mercury, the smallest, densest and least-explored of the terrestrial planets.

NASA shared a video explaining the valley in detail. Check it out below:

(Video courtesy: NASA.gov Video)

(With IANS inputs)