A Jupiter-bound spacecraft is set to fire its engine for an
important maneuver intended to bring it back toward Earth. The
engine burn Thursday afternoon is the first of two maneuvers
planned to set up NASA's Juno spacecraft to use Earth's gravity
to accelerate it toward the outer solar system. The second
engine firing is set for next week and the Earth fly-by will be
in 2013. Juno launched last year from Florida and is due to
arrive at Jupiter in 2016. It's currently about 300 million
miles from Earth. Once in orbit around the poles, Juno will peer
through the cloud cover to learn more about the evolution of the
giant gas planet.