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November 4, 2011

One of the many mysteries about Mars is the origin of its two small moons, Phobos and Deimos. The leading idea says they’re captured asteroids. But some recent research suggests that Phobos could have formed as the result of a collision between Mars and another body.

Settling the issue is one of the goals of Phobos-Grunt, a Russian spacecraft that could launch this month. It’s the first Russian planetary mission in 15 years. The last mission — also to Mars — ended with a booster failure minutes after launch.

If this mission goes as expected, it’ll enter orbit around Mars next year. It’ll release a small Chinese satellite into orbit, then spend months studying Mars as it maneuvers toward Phobos, the larger of the planet’s moons.

Once it’s in position, it’ll gently lower itself to the surface of Phobos, which is only about 25 miles in diameter. A robotic arm will scoop up a few ounces of dust and pebbles, then a small rocket will send them back to Earth. The rest of the lander will then spend months studying the surface of Phobos. Among other things, it’ll analyze the chemistry of the dusty surface.

That experiment, along with analysis of the samples back on Earth, could tell planetary scientists whether Phobos is a child of Mars, or an orphan adopted by the Red Planet.

Mars itself rises in the wee hours of the morning and stands high in the sky at first light, quite near Regulus, the brightest star of Leo. Mars looks like a bright orange star.


Script by Damond Benningfield, Copyright 2011


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