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US Spacecraft Takes New Look at Jupiter on Way to Pluto
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http://enews.voanews.com/t?ctl=16760BD:A6F02AD83191E160AF06974D603954FA9574F7DCC14957C0 NASA's 'New
Horizons' spacecraft makes its closest pass to Jupiter on its 10-year
voyage to Pluto A U.S. spacecraft has taken the closest images of
Jupiter since the Galileo probe perished in a programmed dive into the
huge planet's atmosphere four years ago. The spacecraft's destination
is icy, distant Pluto, but the U.S. space agency NASA wanted to fly
close to Jupiter on the way out to get a scientific update and a speed
boost. VOA's David McAlary reports.







New Horizons spacecraft More than 13 months after its launch, NASA's
New Horizons spacecraft has made its closest pass to Jupiter on its
10-year voyage to Pluto. The head of NASA's science directorate and
chief investigator for the mission, Alan Stern, says the flyby has
been eagerly awaited.

"Between the demise of Galileo with the end of its very successful
mission in 2003 and the arrival of the Juno Jupiter orbiter that we
are all looking forward to in 2016, this is the only train going this
way," said Alan Stern.







Jupiter's Little Red Spot New Horizons has been taking pictures of
Jupiter since January and will continue to dispatch them through June,
but the close pass more than two million kilometers away is giving
astronomers another detailed look at the gas giant, its rings, and its
four biggest moons.

A mission scientist from the Southwest Research Institute in Boulder,
Colorado, John Spencer, spoke of the goals before Wednesday's Jupiter
pass.

"We very carefully tailored our observations so we will be not
repeating things that have have been done by the other seven missions
that have already been to Jupiter," said John Spencer. "Sometimes we
are just looking for changes."







Jupiter flyby trajectoryThe observations have included Jupiter's
auroras and its giant red spot, a swirling centuries-old storm larger
than Earth. New Horizons' advanced instruments have also peered at the
planet's rings in an effort to find more tiny moons. In addition, it
studied the surface composition of the big moons Gannymede; Callisto;
Io, which has a volcano; and Europa, which is thought to have a liquid
water ocean under a shell of ice.

The spacecraft will also become the first to take a trip down the long
tail of Jupiter's magnetosphere, a wide stream of charged particles
extending tens of millions of kilometers.

Alan Stern says the observations are intended as practice for the
duties New Horizons faces at Pluto when it arrives in 2015.

"We have designed this particular flyby to be a stress test on our
spacecraft to work out the kinks so that at Pluto, we do not learn a
thing about our spacecraft, we have worked out those kinks at Jupiter,
putting our spacecraft through 700 different observations," he said.

These observations are only one reason for the visit to Jupiter. The
pass also lets the planet's strong gravity sling it away, providing a
14,000 - kilometer per hour speed boost. This cuts the spacecraft's
flight time to Pluto by three years.

After the Jupiter encounter, New Horizons' electronics will become
dormant for much of its cruise. Mission controllers will shut off all
but the most critical systems and check in once a year to test those
systems, calibrate instruments, and correct the course if needed.