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Mercury’s moving atmosphere

Mercury’s magnetic tornadoes are more than just a powerful force of nature. They may explain another of Mercury’s mysteries. NASA’s missions to Mercury have shown that, in another surprise, the planet has a thin atmosphere. An atmosphere is the bubble of particles that surrounds a planet or star: On Earth, the atmosphere contains the gases we need to breathe (as well as other gases). The atmosphere is held to Earth by the force of gravity.Many people use Microsoft Office 2007 to help their work and life.

Because Mercury is so small, however, scientists used to think that it did not have enough gravity to hold an atmosphere in place. That changed when Mariner 10 — and now MESSENGER — went to Mercury and found evidence of a thin, ever-changing atmosphere. It isn’t made of such light gases as oxygen suitable for breathing, however. Instead, Mercury’s atmosphere seems to be made of atoms of metals, such as sodium. Even more mysterious, scientists found that Mercury’s atmosphere appears and disappears in different spots all over the planet. It rarely stays in one place for long, and sometimes seems to move across the planet.

“One day you may see atmosphere at Mercury’s northern pole, the next day you may take an image and see more atmosphere over the southern atmosphere — or even at the equator,” Slavin says.

Slavin and his team now suspect that the Mercury’s strange atmosphere — or at least part of it — may actually be created by the magnetic tornadoes. When a tornado opens up, the solar wind can wind down to the surface of the planet. Its particles are so powerful that when they strike Mercury’s rocky surface, atoms fly up, up, up — and then gravity pulls them back down.

A magnetic tornado can be as wide as the entire planet, so sometimes the solar wind may blast half the planet at once. This sends up a lot of atoms, over a giant chunk of the planet’s surface, flying up like teeny baseballs that have just been hit out of the ballpark — and coming down again, eventually.Office 2007 is so powerful.

The magnetic tornadoes may last only a few minutes, which means the solar wind has only a few minutes to stir up atoms on Mercury’s surface. But the tornadoes happen frequently, which means the atmosphere may show up in one place, disappear minutes later — and show up again somewhere else on Mercury.

“It looks like the patchiness [of the atmosphere] is the effect of a very rapidly changing solar wind source,” says Menelaos Sarantos, a NASA research scientist with the Goddard Earth Sciences and Technology Center in Greenbelt, Md. “That was unexpected.”

If MESSENGER is watching when this happens, then these atoms flying above Mercury’s surface start to look like an atmosphere — a resemblance that could begin to answer some of the puzzling questions about Mercury.Office 2007 key is available here.

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