Pluto Discovery Day

Two views of Pluto and its moon Charon

Right now, a 1,000 pound spacecraft is streaking toward Pluto at about 30,000 miles per hour relative to Pluto itself. The New Horizons spacecraft was traveling as fast as 51,000 miles per hour (relative to the Sun) after it got a gravity boost by passing close to Jupiter. In July, it will make it closest approach of Pluto and our knowledge of this mysterious body will expand more in the approach and close encounter than it has in all the years before.

It was on this day in 1930 that Clyde Tombaugh discovered Pluto (although it wasn't called by that name until March 24 from a suggestion by 11-year old Venetia Birney of Great Britain). Mr. Tombaugh was the first American to discover a planet (at least it was considered a planet then). I wonder if that was part of the motive for the International Astronomical Union to demote Pluto from being a full-fledged planet?

There are a wide range of instruments aboard the spacecraft and you can find all sorts of other interesting facts about the spacecraft and Pluto on the New Horizons webpage here. The pictures above, although grainy and not very distinct, were taken by New Horizons when it was about 125 million miles from Pluto. So, it's understandable that they are not the best views we have of Pluto and Charon. Don't worry - the pictures will get better!