A NASA spacecraft headed for Pluto will get some assistance from the Hubble Space Telescope in choosing a new object for study once it passes the distant dwarf planet, the space agency says.
Currently past Jupiter on its way to Pluto, the New Horizons exploratory mission will arrive at the dwarf planet around July 2015 to study it and its companion moon Charon, NASA says.
After it finishes its observations there, it will be directed to the Kuiper Belt, a cosmic collection of icy objects -- some the size of Pluto or even larger -- orbiting beyond the dwarf planet in the far reaches of our solar system.
However, choosing just the right target for New Horizons to voyage to next is important because the spacecraft's maneuvering capability is limited and it would need to fire its maneuvering engine by December 2015 to be placed on track for a fly-by of a new target, scientists say.
That's where Hubble comes in. The committee that allocates time on the space telescope has agreed to help find the next target for the NASA spacecraft to head to once it's finished its Pluto mission.
That's a coup for the Pluto mission; time on the Hubble is hard to come by, with astronomers around the world competing for even a few minutes of use of the telescope every year.
Kuiper Belt objects, left over after the formation of the solar system 4.6 billion years ago, have never seen studies in close-up detail because of their extreme distance from our sun.
That makes the chance of using New Horizons for such a mission too good to pass up, scientists say.
Hubble is set to scan a small patch of sky in the region of the constellation Sagittarius to search for possible mission candidates.
Spotting a suitable candidate will not be an easy task, scientists admit. Although Hubble can see to almost the known horizon of the complete universe and can spot entire distant galaxies, the typical Kuiper Belt object is small -- even the largest are no bigger than Manhattan Island -- and reflect very little light.
Still, people with the Hubble program say they're optimistic.
"Hubble can knock this out in a couple of weeks with a 95 percent probability of success," Alan Stern, lead scientists with the Southwest Research Institute in Boulder, Colo., said.
Hubble could perhaps even find more than one Kuiper Belt object that could be reached by the New Horizons spacecraft, he said.
"My fondest hope is we could find a couple or three KBOs and then be in the happy position of having to choose between them," Stern said.
