Brown University | 2018 Nov 20
Computer models developed by Brown University researchers shine a light on the origin of the Mars moon Phobos’ distinctive grooves.
A new study bolsters the idea that strange grooves crisscrossing the surface of the Martian moon Phobos were made by rolling boulders blasted free from an ancient asteroid impact.
The research, published in Planetary and Space Science, uses computer models to simulate the movement of debris from Stickney crater, a huge gash on one end of Phobos’ oblong body. The models show that boulders rolling across the surface in the aftermath of the Stickney impact could have created the puzzling patterns of grooves seen on Phobos today. ...
Phobos’ grooves, which are visible across most of the moon’s surface, were first glimpsed in the 1970s by NASA’s Mariner and Viking missions. Over the years, there has been no shortage of explanations put forward for how they formed. Some scientists have posited that large impacts on Mars have showered the nearby moon with groove-carving debris. Others think that Mars’ gravity is slowly tearing Phobos apart, and the grooves are signs of structural failure.
Still other researchers have made the case that there’s a connection between the grooves and the Stickney impact. In the late 1970s, planetary scientists Lionel Wilson and Jim Head proposed the idea that ejecta — bouncing, sliding and rolling boulders — from Stickney may have carved the grooves. ...
Origin of Phobos Grooves: Testing the Stickney Crater Ejecta Model ~ Kenneth R. Ramsley, James W. Head
- Planetary and Space Science (online 16 Nov 2018) 10.1016/j.pss.2018.11.004