Weird marks on Phobos’ surface are early signs of the end for this moon of Mars.
Mars’ moon Phobos is lined with shallow grooves that stretch across its surface. These grooves were long thought to be fractures caused by the impact that formed a five-mile diameter depression on the moon known as Stickney crater. Now, new modeling supports the view that the grooves are more like "stretch marks" produced by tidal forces, the mutual gravitational pull of the planet and the moon. Orbiting a mere 3,700 miles above the surface of Mars, Phobos is closer to its planet than any other moon in the solar system. As the moon circles Mars, the planet’s gravity draws Phobos inward. Scientists have found these forces acting on Phobos are so strong, they produce more than enough stress to fracture its surface. It's expected that the moon will fall apart in 30 to 50 million years. Watch the video to see a 360-degree view of Phobos.
Please give credit for this item to: NASA's Goddard Space Flight Center Video courtesy of ESA/DLR/FU Berlin Stickney crater image courtesy of NASA/JPL-Caltech/University of Arizona Other images courtesy of ESA/DLR/FU Berlin/G. Neukum
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