BOB HIRSHON (host):
Exotic ice on the surface of Pluto. I’m Bob Hirshon and this is Science Update.
Pluto and its companion objects are so distant that the sun appears to them as just a bright star. But that doesn’t mean they’re frozen stiff. Planetary scientist Hal Weaver at the Applied Physics Lab says that Pluto has vast fields of nitrogen ice that are surprisingly active.
HAL WEAVER (Applied Physics Laboratory, Johns Hopkins University):
You can have these glacier flows and sublimation and condensation cycles taking place at these extremely cold temperatures and we’re seeing all of that.
In the journal Science, he and his colleagues report on the surfaces of all six of the objects in the Pluto system, which includes Charon, Nix, Hydra, Kerberos, and Styx. The smaller objects are surprisingly bright, which could mean that they’re covered in very old but clean water ice. Weaver says spectroscopic data from New Horizons will reach earth soon and reveal whether that speculation is true. I’m Bob Hirshon, for AAAS, the science society.