New Horizons Space Probe Turns For Pluto Flyby

The New Horizons space probe, now less than 1AU (2.96 million miles) from Pluto, performed a complicated engine maneuver to bring it on course for its July 14 flyby. This course correction also sets the record for the farthest distance from earth that such an engine burn has been carried out.

Following commands from the New Horizons Mission Operations Center at the Johns Hopkins University Applied Physics Laboratory through NASA’s Deep Space Network, the 93-second engine thrust reduced the spacecraft’s velocity by 1.14 meters/second.  The maneuver also tweaked New Horizons’ trajectory a little sideways (from the point of view of an observer on earth) to bring it closer to its objective.

At the closest point in the flyby, New Horizons space probe will be about 7,750 miles (12,500 kilometers) from Pluto. It will then fly by Pluto’s largest moon, Charon, at a distance of about 17,900 miles. The mission may be extended by NASA to study one or more Kuiper Belt Objects (KBOs), which are yet to be identified.

New Horizons was launched in 2006 to study Pluto and other objects in the Kuiper Belt. The mission was designed to take advantage of a boost from the gravitational field of Jupiter, which New Horizons passed in 2007 at a speed of 50,000 mph. The spacecraft is also intended to reach its objective before Pluto’s atmosphere freezes as it moves further and further away from the sun in its elliptical orbit.

New Horizons space probe will map the surface features of Pluto and Charon, and their composition using spectroscopy and four-color maps. It will also study their atmospheres. William McKinnon, New Horizons Co-Investigator outlines the complex questions about the outermost reaches of the solar system: “Some KBOs are indeed frozen remnants from the formation of the solar system, and contain clues to the conditions in the solar nebula at a distance of 45 astronomical units or so from the Sun. Most KBOs, however, are immigrants or transplants from closer in, and this includes Pluto-Charon….Pluto and Charon probably formed somewhere in the region between 15 and 35 AU, a zone that overlaps the present orbits of Uranus and Neptune.”

Scientists believe that the solar system was originally much more compact, but also more unstable. Some instability or disturbance flung Neptune and Uranus outwards, and with them Pluto, Charon and many other KBOs. Pluto, its moons and the Kuiper Belt Objects are much more than distant chunks of rock and debris. They contain clues to the formation and evolution of the solar system.