PlutoScientists are already aware that Pluto is really cold, but recent observations suggest that it’s even colder than they had imagined. New radio telescope measurements of Pluto’s surface indicate that it’s a brisk -382 degrees Fahrenheit (scientists had earlier estimated a positively summery -364). Part of the reason for the slight chill in the air – if indeed there was any there – is that Pluto is on the outbound train. The tiny planet’s highly inclined orbit isn’t centered around the sun, while the solar system’s other worlds are more or less centered; part of Pluto’s orbit carries it further away from the sun and “under” the plane shared by the other planets. Curiously enough, however, the surface of Charon – Pluto’s nearly-identical-twin moon – is determined to be warmer than Pluto itself. The readings are taken by the Submillimeter Array in Hawaii by astronomers at the Harvard-Smithsonian Center for Astrophysics.