Pluto looms larger as New Horizons spacecraft closes in

Caption Pluto NASA/JHUAPL/SWRI On Tuesday at 4:49 a.m. PDT, New Horizons will fly by Pluto at 30,800 miles per hour, coming within about 7,750 miles of the dwarf planet. The images it is sending back as it approaches already reveal a complex surface.New Horizons is in the home stretch. With fewer than 500,000 miles and less than a day to go until the NASA spacecraft whizzes by Pluto, the images it’s lobbing back across the roughly 3-billion-mile distance between Earth and Pluto are continuing to turn up fresh surprises.

Pluto was once little more than a blurry dot in the sky; now, the NASA spacecraft’s images reveal a complex surface with signs of ridges and cratering. Geologically speaking,…