I guess astronomers need to make headlines every now and then.
I read this. Interesting story. Phobos orbits Mars every 7.5 hours. It is getting closer to Mars (2 meters every century).
Then, buried in the article, I see Phobos has only 30-50 millions years left. Good thing I got to see pictures before it was gone.
On a related note, there is a crater named Stickney, which, in relation to the diameter of the moon, is enormous.
There are lighter-colored rays emanating from the crater, which astronomers thought was crater ejections. Now, they see that these do not emanate directly from the crater, and think that these are tidal stretch marks. Phobos appears to be a "pile of rubble" loosely held together, and covered with a powdery regolith (had to look that one up). I am surprised the Stickney impact did not blow Phobos apart.
Anyway, as it gets closer to Mars, the strength of gravity on the face closer to Mars will exceed that on the outer side so much, that Mars' gravity will pull the moon apart.
Found the story interesting and thought I would share.
I read this. Interesting story. Phobos orbits Mars every 7.5 hours. It is getting closer to Mars (2 meters every century).
Then, buried in the article, I see Phobos has only 30-50 millions years left. Good thing I got to see pictures before it was gone.
On a related note, there is a crater named Stickney, which, in relation to the diameter of the moon, is enormous.
There are lighter-colored rays emanating from the crater, which astronomers thought was crater ejections. Now, they see that these do not emanate directly from the crater, and think that these are tidal stretch marks. Phobos appears to be a "pile of rubble" loosely held together, and covered with a powdery regolith (had to look that one up). I am surprised the Stickney impact did not blow Phobos apart.
Anyway, as it gets closer to Mars, the strength of gravity on the face closer to Mars will exceed that on the outer side so much, that Mars' gravity will pull the moon apart.
Found the story interesting and thought I would share.
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