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April 9, 2008

Mars' moon Phobos: Ready for its close-up

Posted: 01:01 PM ET

Check out these new views of Mars' moon Phobos, taken by the Mars Reconnaissance Orbiter (MRO) back on March 23.


Source: NASA/JPL-Caltech/University of Arizona

The two images were shot 10 minutes apart. At the time, MRO was a couple hundred miles above the surface of Mars, traveling 7,800 mph. Phobos, which is just 13.5 miles wide, was about 4,000 miles away. Given the distance, the clarity and resolution of the images is remarkable.

The principal feature on the moon is undoubtedly the Stickney crater, on the bottom right in these pictures. It's about 5.5 miles in diameter, and was formed by a very large impactor. Also very noticable is the blue material around the rim.

"Based on analogy with material on our own moon, the bluer color could mean that the material is fresher, or hasn't been exposed to space as long as the rest of Phobos' surface has," said Nathan Bridges with NASA's Jet Propulsion Lab, in a statement.

Mars also has a second, even smaller moon, Deimos. Scientists think the moons might be asteroids from the asteroid belt that got caught in Mars' gravitational field. If so, they are different from Earth's moon, which many scientists think formed from shattered rock jettisoned into space when Earth was hit by a massive asteroid or comet shortly after the planets formed 4.5 billion years ago.

–Kate Tobin, Senior Producer, CNN Science & Technology

Filed under: Mars • NASA • Space

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Larry   April 9th, 2008 2:04 pm ET

Is the fact that it is not all that spherical an indication that perhaps it is relatively young? I’m just a discovery channel schooled planetary observer so I’m probably way off. But it is cool just the same.


Mr. Spock   April 9th, 2008 2:47 pm ET

I have a theory, perhaps Phobos and Deimos were part of a larger body, say the size of Enceladus or Ceres, and then was struck by a collision with an impactor like the one that created the Hellas Basin. When that body cleaved into pieces, they formed Phobos and Deimos. I have a problem with the captured asteroid theory, because you really just don't see this evidence in the Solar System. Moons are ususally victims of collisions and destroyed or reformed.

Mark   April 9th, 2008 2:48 pm ET

Wow, ALF lost a lot of blue paint on that collision. Must have ate more than his fair share of cats that day! Paint & Body shop located on the back side of Phobos...

Justin   April 10th, 2008 3:26 pm ET

Phobos AND Deimos are both theorized to be captured asteroids from the asteroid belt. In fact, one of them, (Phobos, I believe) is in a deteriorating orbit and will slam into the surface of Mars, granted, that's like, 40,000 years from now.

Cataclysmic Binary   April 11th, 2008 12:22 pm ET

Re: Larry

The shape of a celestial body is more indicitive of the mass rather than the age of the body. The problem with both of mars' moons is that neither one is massive enough to be spherical in shape. The more massive an object is, the more gravitational pull. Each part of Phobos pulls on every other part of Phobos. If there was more of it, it would pull itself into a spherical shape. Also other factors play into planetary shape such as angular momentum / rotation, proximity to other large bodies, ect ect. Hope that helps clarify.



Mike   April 11th, 2008 1:23 pm ET

Mars pulled Phobos and Deimos from the asteroid belt in 1877. There is no record of Mars having these moons till then.

Kris   April 11th, 2008 2:45 pm ET

Phobos was left behind during a previous passage of Planet X.

Where are the gold mining aliens? 🙂

Phobos-Isn’t that that chick from Friends? « Youreadireview’s Weblog   April 14th, 2008 1:47 pm ET

[...] that that chick from Friends? Posted on April 14, 2008 by youreadireview is reporting that the Mars Reconnaissance Orbiter(MRO) has take two close-ups of Phobos, [...]

psycogecko   April 14th, 2008 2:30 pm ET

It would be interesting to think, if Mars had oceans, what the tidal forces would have been like with having two moons. Even if they are small, they still would affect tide heights and patterns.

Will   April 15th, 2008 2:20 pm ET

Was this were Doom (the origional PC game) took place? Looks kinda familiar...

Manolo Echeverria   April 15th, 2008 2:51 pm ET

Dis pictures so good. Look like a small rock I find on floor yesterday

Keith   April 15th, 2008 7:37 pm ET

Amazingly the Russians plan to land the Phobos-Grunt probe on this moon to collect samples and return them to Earth. Launch date currently scheduled for October 2009.

Robert   April 15th, 2008 7:44 pm ET

I just want to rotate it. The image looks like its 3D.

selica   April 18th, 2008 11:17 am ET

Phobos looks like a delapidated death star–

maybe it took a good hit during a galactic war and real is a space alien wreck in orbit around mars - imagine what we could learn from somthing like that !

the grist of science fiction

Phobos a moon tormented by space debris that could be a scientific treasure trove - Could a Phobos mars rover land there a examine the surface ?

Franko   April 20th, 2008 3:57 am ET

The Russian probe can check for warming ?
With no atmosphere, stick a probe few meters underground.
Earth data loggers are questionable;
Russians have higher credibility than the Global Warming Activists !

jondoe   April 22nd, 2008 6:40 pm ET

Love those names! Phobos and Deimos = Fear and Terror.

FaTMollY   October 25th, 2008 4:14 am ET

At me such question
I can not change the menu in Windows, it looks on new why that....
Help to adjust... At me of a Window 98

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