NASA’s New Horizons Reaches Pluto

NASA’s New Horizons Reaches Pluto

This NASA image compares the sizes of Pluto (1472 miles in diameter) and its moon Charon with that of Earth.  Launched in 2006, the New Horizons space probe is powered by plutonium. (No surprise there!) It will take 16 months for the probe to transmit all its data to Earth. Investigation of imagery and other data reveal Pluto to be larger than previous estimates. In this video, principal investigator Alan Stern explains the implications on ice composition, rock estimates, and atmospheric composition.