T-14 days and counting to New Horizons Pluto Flyby

180px-New_Horizons_LogoA journey that started 3451 days ago aboard a United Launch Alliance Atlas V is rapidly closing in on its primary destination Pluto. The New Horizons spacecraft will be the first to visit the Pluto system and will bring the distant planet and its five moons to life.

In 14 days it will reach its closest approach to the planet before speeding on further into the Kuiper Belt and eventually another destination (to be decided later).

During the flyby a number of different instruments will be gathering data, it will take more than a year to return all the data to Earth due to how far away the spacecraft is.

The following instruments are on board the spacecraft :-

The Long Range Reconnaissance Imager (“LORRI”) is a long focal length imager designed for high resolution and responsivity at visible wavelengths. The instrument is equipped with a high-resolution 1024×1024 monochromatic CCD imager with a 208.3 mm (8.20 in) aperture giving a resolution of 5 μrad (~1 asec). The CCD is chilled far below freezing by a passive radiator on the antisolar face of the spacecraft. This temperature differential requires insulation, and isolation from the rest of the structure. The Ritchey–Chretien mirrors and metering structure are made of silicon carbide, to boost stiffness, reduce weight, and prevent warping at low temperatures. The optical elements sit in a composite light shield, and mount with titanium and fibreglass for thermal isolation. Overall mass is 8.6 kg (19 lb), with the Optical tube assembly (OTA) weighing about 5.6 kg (12 lb),[29] for one of the largest silicon-carbide telescopes flown at the time (now superseded by Herschel).
Principal investigator: Andy Cheng, Applied Physics Laboratory, Data: LORRI image search at jhuapl.edu

Solar Wind At Pluto (SWAP) is a toroidal electrostatic analyzer and retarding potential analyzer (RPA), that makes up one of the two instruments comprising New Horizons‍ ’​ Plasma and high-energy particle spectrometer suite (PAM), the other being PEPSSI. SWAP measures particles of up to 6.5 keV and, because of the tenuous solar wind at Pluto’s distance, the instrument has the largest aperture of any such instrument ever flown.
Principal investigator: David McComas, Southwest Research Institute

Pluto Energetic Particle Spectrometer Science Investigation (PEPSSI) is a time of flight ion and electron sensor that makes up one of the two instruments comprising New Horizons‍ ’​ Plasma and high-energy particle spectrometer suite (PAM), the other being SWAP. Unlike SWAP, which measures particles of up to 6.5 keV, PEPSSI goes up to 1 MeV.
Principal investigator: Ralph McNutt Jr., Applied Physics Laboratory

Alice is an ultraviolet imaging spectrometer that makes one (of two) photographic instruments comprising New Horizons‍ ’​ Pluto Exploration Remote Sensing Investigation (PERSI); the other being the Ralph telescope. It resolves 1,024 wavelength bands in the far and extreme ultraviolet (from 50–180 nm), over 32 view fields. Its goal is to determine the atmospheric composition of Pluto. This Alice instrument is derived from another Alice aboard the ESA’s Rosetta spacecraft.
Principal investigator: Alan Stern, Southwest Research Institute

The Ralph telescope, 6 cm (2.4 in) in aperture, is one of two photographic instruments that make up New Horizons‍ ’​ Pluto Exploration Remote Sensing Investigation (PERSI), with the other being the Alice instrument. Ralph has two separate channels: a visible-light CCD imager (MVIC- Multispectral Visible Imaging Camera) with broadband and color channels, and a near-infrared imaging spectrometer, LEISA (Linear Etalon Imaging Spectral Array). LEISA is derived from a similar instrument on the EO-1 mission. Ralph was named after Alice’s husband on The Honeymooners, and was designed after Alice.
Principal investigator: Alan Stern, Southwest Research Institute

The Student Dust Counter (SDC), built by students at the University of Colorado Boulder, will operate continuously through the trajectory to make dust measurements. It consists of a detector panel, about 460 mm × 300 mm (18 in × 12 in), mounted on the antisolar face of the spacecraft (the ram direction), and an electronics box within the spacecraft. The detector contains fourteen polyvinylidene difluoride (PVDF) panels, twelve science and two reference, which generate voltage when impacted. Effective collecting area is 0.125 m2 (1.35 sq ft). No dust counter has operated past the orbit of Uranus; models of dust in the outer Solar System, especially the Kuiper belt, are speculative. VBSDC is always turned on measuring the masses of the interplanetary and interstellar dust particles (in the range of nano- and picograms) as they collide with the PVDF panels mounted on the New Horizons spacecraft. The measured data is expected to greatly contribute to the understanding of the dust spectra of the Solar System. The dust spectra can then be compared with those observed via telescope of other stars, giving new clues as to where Earth-like planets can be found in the universe. The dust counter is named for Venetia Burney, who first suggested the name “Pluto” at the age of 11. A thirteen-minute short film about VBSDC garnered an Emmy award for student achievement in 2006.
Principal investigator: Mihaly Horanyi, University of Colorado Boulder

The Radio Science Experiment (REX) will use an ultrastable crystal oscillator (essentially a calibrated crystal in a miniature oven) and some additional electronics to conduct radio science investigations using the communications channels. These are small enough to fit on a single card. Since there are two redundant communications subsystems, there are two, identical REX circuit boards.
Principal investigators: Len Tyler and Ivan Linscott, Stanford University

Next week we will take a look at some of the images that have already been returned as New Horizons approaches Pluto.

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