NASA spacecraft set for first Pluto encounter

WASHINGTON: NASA's New Horizons spacecraft has begun its long-awaited, historic encounter with the dwarf planet Pluto.

The spacecraft is entering the first of several approach phases that culminate on July 14 with the first close-up flyby of Pluto, 7.5 billion kilometres from Earth.

"NASA first mission to distant Pluto will also be humankind's first close up view of this cold, unexplored world in our solar system," said Jim Green, director of NASA's Planetary Science Division at the agency's Headquarters here.

The fastest spacecraft when it was launched, New Horizons lifted off in January 2006. It awoke from its final hibernation period last month after a voyage of more than 3 billion miles, and will soon pass close to Pluto, inside the orbits of its five known moons.

In preparation for the close encounter, the mission's science, engineering and spacecraft operations teams configured the piano-sized probe for distant observations of the Pluto system that start January 25 with a long-range photo shoot.

The images captured by New Horizons' telescopic Long-Range Reconnaissance Imager (LORRI) will give mission scientists a continually improving look at the dynamics of Pluto's moons.

The images also will play a critical role in navigating the spacecraft as it covers the remaining 220 million kilometres to Pluto.

"We've completed the longest journey any spacecraft has flown from Earth to reach its primary target, and we are ready to begin exploring," said Alan Stern, New Horizons principal investigator from Southwest Research Institute in Colorado.

LORRI will take hundreds of pictures of Pluto over the next few months to refine current estimates of the distance between the spacecraft and the dwarf planet.

Though the Pluto system will resemble little more than bright dots in the camera's view until May, mission navigators will use the data to design course-correction manoeuvres to aim the spacecraft towards its target point this summer. The first such manoeuvre could occur as early as March.