[UCANSEE2]

Captured moon.

My theory: Phobos is a comet/asteroid that was captured by Mars. The large 'crater' is actually the head of the comet which was burning as it traveled through our solar system. The grooves paths from the burning plasma. The reason for grooves which do not follow the 'pattern' of the others is that the comet made multiple passes by the Sun and the other grooves are much older and their origin 'crater' is gone.

Here is asteroid VESTA. See the grooves ?

[Kirkwood]

Comets are balls of ice and rocks. They aren’t made of plasma and they don’t burn.

[Vaquero]

This moon has so little gravity that the boulders that supposedly made the groves would have had to be enormously heavy to not bounce off the surface