Posted on 07/04/2016 6:40:49 PM PDT by BenLurkin
Phobos and Deimos are both small for moons — about 14 and 7.7 miles (22.5 and 12.4 kilometers) wide, respectively — and sort of potato-shaped. Compared to other satellites in the solar system, they look more like asteroids. As a result, astronomers previously hypothesized that these moons were asteroids captured by Mars' gravitational pull.
...previous research suggested that Phobos and Deimos would have relatively irregular orbits. In reality, these moons have nearly circular orbits positioned near the Martian equator.
... huge impact that previous research suggested created the gigantic Borealis basin in the northern lowlands of Mars, which covers two-fifths of the Red Planet's surface. Prior work suggested that this basin is an impact crater, created when an impactor about 1,200 miles (2,000 kilometers) wide struck Mars, generating a ring of debris around the Red Planet with a mass of about 110 quadrillion tons (100 quadrillion metric tons), or about 10,000 times the combined mass of Phobos and Deimos.
The research team's computer models suggested that, over time, in the inner part of this debris ring where the rubble was most densely packed, large moons up to hundreds of miles in diameter would have clumped or accreted together. In contrast, in the outer part of the debris ring, dust and rocks were thinly dispersed, making it difficult for this material to accrete into moons.
However, the scientists found that gravitational tugs from one or more large moons from the inner debris ring could have stirred up rubble in the outer ring, shepherding rock and dust to form smaller outer moons, such as Phobos and Deimos. The researchers calculated that after about 5 million years, Mars' gravitational pull would have doomed the other moons, sending them crashing to the Red Planet's surface and leaving Phobos and Deimos as the sole survivors.
(Excerpt) Read more at space.com ...
daybree rings become moons .. sometimes.. could they be remnants or part of other catastrophic events related to a once vibrant and prosperous Mars? Ya never know.
Good book. Good flick
Screw Mars. It’s dead. Jupiter is King. Juno should be transmitting data soon.
Keeping fingers crossed. Braking requires a 35 rocket burn.
Heaven knows I’m no rocket scientist, but 35 minutes seems like a very long burn for any rocket engine.
Thanks BenLurkin.
Mars was hit by a great big bolide at least once -- it was sufficient to produce most of the craters in the Hemisphere of Craters, through impact by fragments, or by ejecta. The rest in that half of the surface, and almost all in the Opposite Hemisphere were formed basically one at a time over a long period.
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Red Planet’s Ancient Equator Located (esp. pertinent)
http://www.freerepublic.com/focus/chat/1390424/posts?page=53#53
At this point what difference does it make.
Phobos is not a moon. It’s an abandoned space ship!
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