Video: Pluto scientist’s biggest surprise so far

A four-planet system orbiting the star Kepler-223 in the constellation Cygnus is actually a rarity: Its planets, all miniature Neptunes nestled close to the star, are orbiting in a unique resonance that has been locked in for billions of years. For every three orbits of the outermost planet, the second orbits four times, the third six times and the innermost eight times.

The first hints of dramatic cliffs, chasms and craters are showing up in new imagery of Pluto and its Texas-sized moon Charon as NASA’s New Horizons spacecraft prepares to bolt by the icy worlds Tuesday.

NASA’s New Horizons spacecraft, speeding toward deeper space at more than 32,000 miles per hour, has successfully performed a series of targeting manoeuvres that set it on course for a January 2019 encounter with Kuiper Belt object 2014 MU69. This ancient body is more than a billion miles beyond Pluto. The propulsive manoeuvres were the most distant trajectory corrections ever performed by any spacecraft.