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Washington
04 July 2008
Data from the first flyby of the planet Mercury in January of 2008 bythe spacecraft MESSENGER are reported in eleven papers this week in thejournal Science. The findings reveal new details about the solarsystem's smallest planet 77 million kilometers from Earth. VOA'sJessica Berman reports.
During its close encounter withMercury on January 14, MESSENGER's seven instruments collected data onthe planet's surface, its enormous magnetic interior and wispyexosphere.
Among the findings - Mercury's surface is made ofsmooth planes produced by lava flows and explosive eruptions billionsof years ago.
Scientists say the volcanic activity is responsible for huge craters on the surface similar to those on the Moon and Mars.
Jim Head is a planetary geologist at Brown University in Rhode Island and lead author of one of the studies.
Headsays astronomers are interested in studying Mercury, the planet closestto the Sun, because so little is known about the formation of Earth,which is very young compared to Mercury.
"Now that we haveevidence for volcanism, we're starting to find a rich planetary exampleof these transitions between the early history of the planets and thelater history that we observe on the Earth," said Jim Head. "So, fromthat sense, Mercury with these new data, and what we'll see as we havetwo more encounters and go into orbit, is really going to take itsplace in filling the pictures to those early chapters of the earlysolar system. And they are totally relevant to what the conditionswere on the Earth that led to where we are today."
The spaceprobe will make two more flybys, one more in October of this year andat the end of September 2009, before settling into permanent orbitaround Mercury in 2011.
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