Mission Elapsed Time:
Beginning 1/19/06 19:00:00 UTC
2705 Days (7.41 yrs.) 06 Hours 11 Minutes
Pluto Closest Encounter
Operations Begins:
4/12/15 00:00:00 UTC
636 Days (1.74 yrs.) 22 Hours 47 Minutes
Pluto Closest Approach:
7/14/15 11:49:59 UTC
757 Days (2.03 yrs.) 10 Hours 36 Minutes
New Horizons Team Sticking to Original Flight Plan at Pluto:
Unless significant new hazards are found, expect NASA’s New Horizons spacecraft to stay on its original course past Pluto and its moons, after mission managers concluded that the danger posed by dust and debris in the Pluto system is less than they once feared.
The New Horizons team recently completed an 18-month study of potential impact hazards – mostly dust created by objects hitting Pluto’s small satellites – the spacecraft would face as it speeds some 30,000 miles per hour (more than 48,000 kilometers per hour) past Pluto in July 2015. The team estimated that the probability of a mission-ending dust impact was less than 0.3 percent if the spacecraft followed the current baseline plan, far below some early, more conservative estimates. So, with the concurrence of an independent review panel and NASA, the project team expects to keep New Horizons on this baseline course, which includes a close approach of about 12,500 kilometers (nearly 7,800 miles) from the surface of Pluto.
“We found that loss of the New Horizons mission by dust impacting the spacecraft is very unlikely, and we expect to follow the nominal, or baseline, mission timeline that we've been refining over the past few years,” says New Horizons Project Scientist Hal Weaver, of the Johns Hopkins University Applied Physics Laboratory. “Still, we'll be ready with two alternative timelines, in the event that the impact risk turns out to be greater than we think.”
Safe passage: With the dust-impact hazard less than once feared, the New Horizons team plans to keep its spacecraft on the baseline trajectory through the Pluto system.
Those alternate plans (called SHBOTs, short for Safe Haven by Other Trajectories) are being developed should new information – gathered from New Horizons camera observations during the approach to Pluto, for example, or new dust-dynamics analyses – indicate less-than-smooth sailing for New Horizons. New Horizons managers recently presented their impact-hazard outlook and if-necessary mitigation plans to an independent NASA review panel and to the NASA Science Mission Directorate Program Management Council and received endorsements from both.
New Horizons Course and Position in Three Dimensions:
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New Horizons Principal Investigator Alan Stern, of the Southwest Research Institute, says the mission team is now finalizing plans for the Pluto encounter. In early July, the team will rehearse the most critical nine-day segment of the baseline encounter plan, putting itself and the spacecraft through the paces of the flight toward and just past Pluto and its moons. Stern adds that the spacecraft remains on target for a close approach to Pluto in 2015, all subsystems are performing nominally, and “the anticipated science observations will revolutionize our understanding of dwarf planets and the Kuiper belt, and excite a whole new generation of the public to the first reconnaissance of a planet on the very frontier of our solar system
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