The New Horizons spacecraft, set to fly by Pluto in the summer of 2015, needs a study target to visit after its Pluto expedition, and Hubble is going to help it find the best target possible.
The spacecraft, which was launched in 2005, has limited options due to the restraints on ground-based telescopes. Its goal was to study interesting objects in the Kuiper Belt, a large area of space filled with icy remains left over from the origin of the solar system, 4.6 billion years ago. Unfortunately objects in this area are generally too dark and (relatively) small to find from the ground.
NASA's Hubble Space Telescope is now assigned to the New Horizons project to find a KBO appropriate for the spacecraft to visit. The object will have to be on the New Horizons' flight trajectory, as fuel is limited. Specifically, Hubble needs to find a suitable object in the direction of the Sagittarius constellation, a bright, thick background bound to make the task challenging.
"It really is kind of a fishing trip," Hubble spokesman Ray Villard told NBC News.
Never before has anyone or anything visited Kuiper Belt Objects (KBOs), due to the belt's distance from the sun-a whopping 3 billion miles. If Hubble finds at least two interesting objects in 40 orbits, it will continue its search for another 160 orbits, according to principal investigator for the New Horizons project, Alan Stern.
Hubble will orbit at predicted KBO speeds to attempt to distinguish objects in the starry background. The telescope, which supported NASA's Mars missions, asteroid missions and aided Pluto exploration, is so powerful it can "see galaxies near the horizon of the universe."
Astronomers compete relentlessly to get "Hubble time" for their projects. To require Hubble use, projects must target goals that can only be achieved by Hubble's out-of-this-world capabilities. The telescope found oceans on Europa, a moon orbiting Jupiter, and most recently helped identify Pluto's largest moon, Charon, which shows evidence of once containing a subsurface ocean. Pluto and Charon are part of New Horizons' 2015 mission.
"The planned search for a suitable target for New Horizons further demonstrates how Hubble is effectively being used to support humankind's initial reconnaissance of the solar system," says Matt Mountain, director of the Space Telescope Science Institute, in the Hubble press release. NASA predicts a 95% chance of success for Hubble.
The search for a KBO, which began even before the news was released, will hopefully help New Horizons boldly go where no probe has gone before.