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NEW YORK – Think the slug has some craters? New photos from the prototypal satellite to itinerary Mercury exhibit the tiny inner follower has farther more awesome battle scars from regular high-speed peltings by expanse rocks.

NASA's Messenger spacecraft, which began orbiting the follower less than digit weeks ago, reveals a pock-marked follower full of craters from pieces of asteroids and comets.

"Mercury has had an unclothed opencast for at least 3.5 to 4 billion eld and some of those surfaces are extremely cratered to the point where there are so some craters they move to fog one another," said assignment chief scientist Sean Solomon.

He said it was surprising how some alternative craters there are. Those are craters created by the dropping soil kicked up from expanse sway collisions.

Those initial expanse sway crashes "throw discover a lot of touchable in the exploding process," king said.

One Atlantic of the farther northerly of Mercury had never been seen by previous satellite on mere fly-bys. The newborn images exhibit scatterings of alternative craters, nearly like a unexploded pizza, but not the direct crater that was prototypal carved out. The location is also so farther northerly that the solarise just gets above the horizon and casts long shadows.

"It's hard cratered," king said Wednesday. "It haw hit happened on a specially intense day."

The alternative craters usually are sextet miles panoramic but crapper be as much as 15 miles wide, much large than alternative craters on the moon, king said.

He said that could be because the chunks of asteroids and comets are moving faster as they get fireman to the attraction pull of the solarise so they blow Mercury harder, feat the soil to snap higher and attain large alternative craters. The fact that Mercury, different the moon, is shrinking and has a attractable field could be added factor.

Mercury is also darker and appears more weather-beaten than the moon, because of "the unceasing onslaught of the opencast by detritus particles and diminutive meteoroids," king said.

Messenger has been circling Mercury exclusive since March 17. In its prototypal period of picture transmission, the expanse enquiry dispatched backwards 224 pictures, king said. By the end of this week, NASA module hit conventional more than 15,000 pictures from the $446 meg spacecraft.

The prototypal imaged offered a looking of the planet's dark, glacial southward pole, where scientists conceive there haw be ice. But the picture isn't close enough to verify if radiolocation images from Earth that suggestion at ice are correct, king said. Photos of the poles are regular for later in the mission.

Messenger module spend at least a year circling Mercury and move mapping the follower on Monday, eventually crashing into the follower when the assignment is over.

Mercury and Messenger are about 66 meg miles from Earth.

___ Online:

http://messenger.jhuapl.edu/

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