So then, what about all those lines on Phobos?

[Duer 157099]

My first thought, upon seeing this image of Phobos, is that it reminded me of the "mysterious" lines from the sailing stones around The Racetrack Playa in Death Valley.

But really, I have no idea what might cause these lines on Phobos.

Thoughts?

http://en.wikipedia.org/wiki/Racetrack_Playa

http://www.esa.int/SPECIALS/Mars_Express/SEMK17CKP6G_0.html#subhead3

http://www.esa.int/images/6_7926_phobos_nadir_large,0.jpg

[daleanime]

1. I think....

we need to go check it out in person:evilgrin:

[thereismore]

2. They are young features, which means they happened long after Phobos was made. nt

[Duer 157099]

3. Yeah, but, what are they?

If you go to the link you can see the hi res version and there are just tons of these lines, and they continue right through the craters.

This rock seems much too small to not be knocked off kilter if space debris has impacted it that often.

Anyone know what the official line is about it? Tracks of meteorites?

[thereismore]

10. No idea. nt

[foxfeet]

4. Laugh lines and crow's feet.

[mindwalker_i]

5. Maybe Phobos wasn't feeling good a while back...

We should send it some antidepressants.

[Duer 157099]

6. Junkie tracks?

Poor phobos!

[IndianaGreen]

11. Poor Mars! Phobos is on a degrading orbit and will crash into Mars in the future!

The same can be said for Deimos, which like Phobos, is a captured asteroid from the asteroid belt.

[HysteryDiagnosis]

12. Mars suffers from a hemispheric dichotomy, pity that. n/t

[Psephos]

7. Best explanation is that they're shock-wave compression lines.

Phobos and Deimos are younger than Mars. They coalesced in orbit well after Mars formed from the Solar Cloud. Jupiter's moon Almathea is another example of a second-generation body in the Solar System.

Gravitational instruments on Mars probes show that Phobos is not dense enough to be solid all the way through. Instead, it must be roughly a third empty space between the fragments that its weak gravity holds together. In other words, it's little more than a ‘rubble pile’ circling Mars. Such a rubble pile would be composed of a jumble of blocks, some huge, most small, all pressing close, with spaces between them where they do not fit easily together.

The lines can be correlated with impact sites. Think of them as analogous to the cracks that form in a windshield after impact with a stone on the freeway. The shock waves from a big impact would radiate radially away from the impact site, and their compressive force would vibrate and settle the rock fragments in their path into a more compact arrangement, just as shaking a jar of peanuts settles the peanuts down into the jar in a more compact arrangement.

Here are some good pics that shows the correlation of a major set of lines with a major impact site.

[tridim]

9. Those images are crazy! Thanks for posting them.

[HysteryDiagnosis]

8. Remnants of a supercross perhaps.... or something altogether

different.

http://www.youtube.com/watch?v=-l3x4QDWxmc