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New Horizons Pluto-Kuiper Belt mission

  • New Horizons spacecraft
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  • New Horizons probe
    New Horizons is a NASA mission to explore Pluto, its largest moon Charon, and the Kuiper Belt. Designed and built at the Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, New Horizons was launched from Cape Canaveral Air Force Station on January 19, 2006.

    Having launched before the critical date of February 3 allowed New Horizons to take advantage of a gravity-assist (a slingshot effect) from Jupiter, in early 2007, to boost its speed to about 51,000 mph (23 km/s) – a spacecraft record. The Jupiter flyby trims the trip to Pluto by five years, enabling arrival at Pluto-Charon in July 2015. It also provides an opportunity to test the spacecraft's instruments and flyby capabilities on the Jupiter system.

    New Horizons will conduct a five-month-long study of the Pluto system, as it approaches, fly past (closest approach on July 14, 2015), and recedes from its target. It will study the global geology and geomorphology of Pluto and Charon, map their surface compositions and temperatures, and examine Pluto's atmospheric composition and structure.

    The spacecraft also will study the family of small moons recently discovered in orbit around Pluto (for details see Pluto, moons). Then New Horizons will then head deeper into the Kuiper Belt to investigate one or more of the icy mini-worlds in this vast region, at least a billion miles beyond Neptune's orbit.

    New Horizons trajectory

    The spacecraft

    The 1,050-pound, piano-sized probe was launched on January 19, 2006, by an Atlas V rocket, then given a final boost by a kick-stage solid propellant motor. It achieved the highest Earth escape velocity of any spacecraft 57,600 km/h (35,800 mph), reaching lunar orbit distance just nine hours after third stage separation and on track to surpass the distance of Jupiter 13 months later. (See fastest spacecraft).

    The New Horizons science payload, developed under direction of Southwest Research Institute, includes imaging infrared and ultraviolet spectrometers, a multi-color camera, a long-range telescopic camera, two particle spectrometers, a space-dust detector and a radio science experiment. The dust counter was designed and built by students at the University of Colorado, Boulder.

    The spacecraft will "sleep" in electronic hibernation for much of the cruise to Pluto. Operators will turn off all but the most critical electronic systems and monitor the spacecraft once a year to check out critical systems, calibrate instruments and perform course corrections, if necessary.

    The spacecraft will send back a beacon signal each week to give operators an instant read on spacecraft health. The entire spacecraft, drawing electricity from a single radioisotope thermoelectric generator, operates on less power than a pair of 100-watt household light bulbs.

    Science payload

    New Horizons science instruments
    The science payload includes seven instruments:
    • Ralph: Visible and infrared imager/spectrometer; provides color, composition and thermal maps
    • Alice: Ultraviolet imaging spectrometer; analyzes composition and structure of Pluto's atmosphere and looks for atmospheres around Charon and Kuiper Belt Objects
    • REX: (Radio Science EXperiment) Measures atmospheric composition and temperature; passive radiometer
    • LORRI: (Long Range Reconnaissance Imager) telescopic camera; obtains encounter data at long distances, maps Pluto's farside and provides high resolution geologic data
    • SWAP: (Solar Wind Around Pluto) Solar wind and plasma spectrometer; measures atmospheric "escape rate" and observes Pluto's interaction with solar wind
    • PEPSSI: (Pluto Energetic Particle Spectrometer Science Investigation) Energetic particle spectrometer; measures the composition and density of plasma (ions) escaping from Pluto's atmosphere
    • SDC: (Student Dust Counter) Built and operated by students; measures the space dust peppering New Horizons during its voyage across the solar system


    Feb. 28, 2007: Closest approach to Jupiter.

    Jan. 20, 2006: Mission principal investigator announced that some of the ashes of Clyde Tombaugh, discoverer of Pluto, are being carried aboard the spacecraft.

    Jan. 19, 2006: New Horizons was successfully launched at 1900 GMT.

    Speeds of Pioneers 10 and 11, Voyagers 1 and 2, and New Horizons relative to the Sun.

    External sites

    New Horizons home page at Johns Hopkins
    New Horizons home page at NASA

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    Source: NASA