New Horizons and IceHunter

As the NASA New Horizons mission edges ever closer to Pluto astronomers have turned to the global community to help identify the next mission target. Despite traversing the entire Solar System to reach Pluto and its moon Charon, the intrepid robotic spacecraft will have enough fuel remaining to possibly travel a further billion kilometres and into the Kuiper Belt.

After passing Pluto and Charon, pending NASA approval of an extended mission, the spacecraft can retarget itself for an encounter with a Kuiper Belt Object (KBO). The KBO target will not be selected until shortly before the Pluto encounter, but scientists hope to find one or more that the spacecraft can reach that are at least 30 miles (about 50 kilometers) across. This encounter would be similar to the Pluto-Charon encounter; the spacecraft would map the KBO with high resolution images, investigate its composition using infrared spectroscopy and four-colour maps, and look for an atmosphere and moons.

The IceHunters is the latest project in the ever growing Zooniverse collection. The main goal is to discover Kuiper Belt Objects with just the right orbit and just the right characteristics to make them eligible for a visit from the mission. At this time, the space probe has enough fuel in reserve to allow up to two different objects to be visited.

Astronomers working with the mission team are taking thousands of images, each of which contains tens of thousands of stars, along with many asteroids and Kuiper Belt objects on orbits that cannot be reached by the spacecraft. Astronomers working at two different locations take images of the sky a few hours apart and these are then subtract from each other to remove objects shining at a constant brightness such as stars and galaxies.

The New Horizons probe will reach Pluto in 2015 and hopefully its secondary target sometime between 2016 and 2020.