This month marks a warm up spell for the New Horizons spacecraft currently on its way to Pluto. Launched January 19th 2006, this mission is now covering a million kilometres a day as it heads to the Pluto system for a rendezvous in July 2015.
The discovery last summer of yet another moon of Pluto has the science team a mite worried –not so much about the new moon- referred to as Pluto IV, but about a possible debris cloud around the whole system. When the spacecraft reaches Pluto it will be zipping along at a flyby speed of 14 kilometres-per-second. At that rate, even particles less than a milligram can penetrate the micrometeoroid blankets and do a lot of damage to electronics, fuel lines and sensors.
When New Horizons was being designed – the last in a long series of almost missions to Pluto, only one satellite of the little dwarf planet was known – Charon. Charon is the ferryman of the dead, closely associated in myth with the Greek god Hades, whom the Romans identified with their god Pluto. The name of this moon of Pluto is a tricky one to pronounce…the translation from the Greek gives Karon – but the discoverer of the moon uses Sharon- in part as a nod to his wife’s name- Charlene. The New Horizons team uses the soft sh version.
The two moons discovered in 2005 are known as Nix (the Greek goddess of darkness and night, and mother of Charon) and Hydra (the nine-headed serpent who battled Hercules). Both of these moons are much smaller than Charon; Hydra is only about 60 km across. New Horizons is now closer to them than any other spacecraft – it broke the old record set by Voyager 1 in 1986 in early December last year. It will be able to image them as it approaches in 2015, but for now, they are just too small and too far away for New Horizon to get a good look.
So it’s back to Earth and near Earth to see what’s up ahead – the hunt for the, as yet undiscovered, satellites and rings will be carried out by the Hubble Space Telescope, some very large ground-based telescopes and ALMA – a radio telescope array in Chile that is still being completed. The general public can get involved in the New Horizons project with an offshoot of the ever popular Galaxy Zoo. Ice Hunters invites everyone to help sift through images to find possible Kuiper Belt objects that New Horizons might go on to visit after its flyby of Pluto. Of course the images are full of stars and fast moving asteroids, so finding a slow ice blob is, as the website states: “like looking for a needle in a haystack that also contains a bunch of pins.”
This episode of “What is the Stars” was first broadcast January 9, 2012. Listen live on Mondays and Fridays at 22:45 on lyric fm
