NASA's New Horizons spacecraft is locked and loaded for its historic July 14 flyby of Pluto — and on Tuesday, the science team behind the $728 million mission celebrated the switch to encounter mode with cheers and applause.
The start of the Pluto flyby sequence means that the piano-sized probe will plow ahead on its predetermined course, coming within 8,000 miles (12,500 kilometers) of the dwarf planet's surface at 7:49 a.m. ET July 14, even if it experiences glitches like the one that occurred on the Fourth of July.
If trouble occurs, the spacecraft is programmed to reboot itself and resume its tasks without intervention from Mission Control at Johns Hopkins University's Applied Physics Laboratory in Maryland. That level of autonomy is crucial because New Horizons is now almost 3 billion miles away from Earth. If the spacecraft had to turn to its controllers for help, it would take 4.5 hours to send a distress call at the speed of light, and another 4.5 hours for the fix to be sent from Earth back to New Horizons.
The switch to encounter mode also means that science observations are resuming, and it shouldn't be long before fresh imagery of Pluto and its moons starts popping up again on the New Horizons LORRI image database. To keep on top of developments, check in with the New Horizons websites at NASA and APL (plus DailyPluto.com on Facebook).