New Horizons mission less than one year from Pluto
July 14 marked exactly one year until the New Horizons mission will conduct the Pluto system, inaugurating the “Year of Pluto.” At a two-day quarterly Science Team Meeting, held at the Johns Hopkins University Applied Physics Lab in Laurel, MD, mission staff celebrated with a “P Minus One” reception on Tuesday evening.
On Wednesday night, the public portion of the “Year of Pluto” kicked off with talks by New Horizons Principal Investigator Dr. Alan Stern, Science Team Co-Investigator William McKinnon and science writer Dava Sobel at the Smithsonian National Air and Space Museum in Washington, D.C. The event can be viewed here: NASM Science Team Meeting
Even though it will not be seen up close for a year, the Pluto system is receiving interest by the media. There have been calls for a reconsideration of Pluto’s planetary status in light of the fact that it has five known moons and an atmosphere that never completely disappears during its 248-year solar orbit.
David Eicher, editor of Astronomy magazine, publicly called for a debate between Stern and Dr. Neil deGrasse Tyson, director of the Hayden Planetarium at New York’s American Museum of Natural History. Astronomy offered to host the debate and engage its readers throughout the process. Eicher’s statement echoed a challenge Stern issued Tyson several weeks ago for a debate on the subject of planet definition. Tyson turned down the offer.
Launched on January 19, 2006, New Horizons has been traveling eight-and-a-half years and recently crossed Pluto’s perihelion, the planet’s closest point to the Sun in its elliptical orbit. Mission team members now describe the probe as being “in Pluto space.”
Mission team members conducted a minor course correction of the probe on July 14, speeding it up approximately 2.4 miles per hour. Without this maneuver, New Horizons would arrive at the Pluto system 36 minutes later than planned for next year’s encounter.
Describing the burn as “flawless,” Stern said, “You could say that New Horizons just lit a little candle for its one year out anniversary.”
This was the sixth course correction since New Horizons’ launch. It used up only a quarter of a kilogram of fuel, less than half of one percent of the 53 kilograms of fuel still onboard.
Still searching for a Kuiper Belt Object to visit after Pluto, the New Horizons team was awarded 160 hours of observing time on the Hubble Space Telescope after a trial 40-orbit period in June turned up two potential targets. This was after ground-based telescopes failed to find a target Kuiper Belt Object in New Horizons’ trajectory.
Onboard the piano-sized spacecraft are seven science instruments. These are the ALICE Ultraviolet Spectrograph; the RALPH Visible Color Imager (MVIC) and Infrared Spectral Imager (LEISA); the REX Radio Experiment Antenna and Processing Card; the Long Range Reconnaissance Imager (LORRI) and Panchromatic Visible Imager; the Pluto Energy Particle Spectrometer Science Investigation (PEPSSI); the Solar Wind at Pluto (SWAP); and the Venetia Burney Student Dust Counter (VB-SDC).
The VB-SDC was constructed by students at the University of Colorado as well as other academic institutions.
Together, these instruments will be employed to carry out the mission’s primary objectives, which include mapping the surfaces of both Pluto and its largest moon Charon, characterizing the geology of these two objects, characterizing Pluto’s tenuous atmosphere and determining the rate at which it is escaping, searching for an atmosphere on Charon, mapping surface temperatures on both Pluto and Charon, and searching for rings and additional moons in the system.
New Horizons has an additional goal of the mission will be to conduct similar studies of one or more Kuiper Belt Objects beyond Pluto.
The duration of the flyby has been divided into seven distinct phases, three approach phases, three departure phases, and the near-encounter phase.
Approach Phase 1 begins in January and runs through early April. Approach Phase 2, which runs from early April through mid-June is when New Horizons will first send back photos of the Pluto system better than those taken by the Hubble Space Telescope. Approach Phase 3 goes from mid-June to one day before the encounter.
The Near Encounter Phase is short, from one day before closest approach to one day after. At this point, the spacecraft will be gathering the most detailed information related to the goals above.
Departure Phase 1 will then kick in, running through early August, followed by Departure Phase 2, which is scheduled to last through late October, Departure Phase 3 is slated to last until the end of 2015.
Because so much of the spacecraft’s power upon approach is being used to gather information, the entirety of the data it collects will be take another year to be returned to Earth.
But before 2015, New Horizons will celebrate another important milestone. On August 25, exactly 25 years to the day of Voyager 2’s 1989 flyby of Neptune, New Horizons will cross Neptune’s orbit.
Video courtesy of NASA
Laurel Kornfeld is an amateur astronomer and freelance writer from Highland Park, NJ, who enjoys writing about astronomy and planetary science. She studied journalism at Douglass College, Rutgers University, and earned a Graduate Certificate of Science from Swinburne University’s Astronomy Online program. Her writings have been published online in The Atlantic, Astronomy magazine’s guest blog section, the UK Space Conference, the 2009 IAU General Assembly newspaper, The Space Reporter, and newsletters of various astronomy clubs. She is a member of the Cranford, NJ-based Amateur Astronomers, Inc. Especially interested in the outer solar system, Laurel gave a brief presentation at the 2008 Great Planet Debate held at the Johns Hopkins University Applied Physics Lab in Laurel, MD.