Data from the first flyby of the planet Mercury in January of 2008 by
the spacecraft MESSENGER are reported in 11 papers this week in the
journal "Science." The findings reveal new details about the solar
system's smallest planet 77 million kilometers from Earth. VOA's
Jessica Berman reports.
During its close encounter with
Mercury on January 14, MESSENGER's seven instruments collected data on
the planet's surface, its enormous magnetic interior and wispy
Among the findings - Mercury's surface is made of
smooth planes produced by lava flows and explosive eruptions billions
of 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.
says astronomers are interested in studying Mercury, the planet closest
to the Sun, because so little is known about the formation of Earth,
which is very young compared to Mercury.
"Now that we have
evidence for volcanism, we're starting to find a rich planetary example
of these transitions between the early history of the planets and the
later history that we observe on the Earth," he said. "So, from
that sense, Mercury with these new data, and what we'll see as we have
two more encounters and go into orbit, is really going to take its
place in filling the pictures to those early chapters of the early
solar system. And they are totally relevant to what the conditions
were on the Earth that led to where we are today."
probe will make two more flybys, one more in October of this year and
at the end of September 2009, before settling into permanent orbit
around Mercury in 2011.