NASA’s New Horizons Probe Reaches Pluto

Tuesday was a historic occasion for space exploration as NASA’s New Horizons probe reached it's closest point to the dwarf planet Pluto. 

The probe past the distant world at over 28,000 mph at 7:49 am ET, within 7,770 miles of Pluto’s surface. The first images taken from New Horizons show Pluto in shades of red and orange, somewhat resembling the planet Mars. Visible are deep valleys, mountains, and craters on a fairly young planetary surface which could indicate geological activity. Research shows Pluto to have a thin nitrogen atmosphere which leaks far out beyond the dwarf planet's surface. Pluto is also larger than previously thought, at 1,470 miles across.

New Horizons' mission began in January 2006. Shortly after, astronomers at the International Astronomical Union voted to change the definition of the word “planet”, a move that downgraded Pluto to the more diminutive “dwarf planet”.