Pluto Close-Up: Spacecraft Makes Flyby Of Icy World

Members of the New Horizons science team react to seeing the spacecraft's last and sharpest image of Pluto before closest approach later in the day, Tuesday, July 14, 2015 at the Johns Hopkins University Applied Physics Laboratory. (Bill Ingalls/NASA via AP)

We've made it to Pluto by NASA's calculations, the last stop on a planetary tour of the solar system a half-century in the making.

The moment of closest approach for the New Horizons spacecraft came at 7:49 a.m. EDT Tuesday, culminating a journey from planet Earth that spanned an incredible 3 billion miles and 9½ years.

Based on everything NASA knows, New Horizons was straight on course for the historic encounter, sweeping within 7,800 miles of Pluto at 31,000 mph. But official confirmation won't come until Tuesday night, 13 nerve-racking hours later. That's because NASA wants New Horizons taking pictures of Pluto, its jumbo moon Charon and its four little moons during this critical time, not gabbing to Earth.