to New Horizons is a space probe launched by NASA on 19 January 2006 to study the dwarf planet Pluto and the Kuiper belt. It is expected to be the first spacecraft to fly by and study Pluto and its moons, Charon, Nix, Hydra, Kerberos, and Styx, with an estimated arrival date at the Pluto–Charon system of 14 July 2015. As of 21 January 2014, its distance from Pluto is about 4.29 AU (about 29.33 AU from Earth), with radio signals taking 4 hours to travel to the spacecraft from Earth (an 8 hour round trip).
Launched directly into an Earth-and-solar-escape trajectory with an Earth-relative velocity of about 36,373 mph it set the record for the highest velocity of a human-made object from Earth. Using a combination of monopropellant and gravity assist, it flew by the orbit of Mars on 7 April 2006, Jupiter on 28 February 2007, the orbit of Saturn on 8 June 2008; and the orbit of Uranus on 18 March 2011. Its secondary mission is to fly by one or more other Kuiper belt objects (should a suitable target be available) then the heliosphere. It is expected to become the fifth interstellar probe and second fastest in the history of space exploration.But it wouldn't reach the two Voyagers 1 and 2.
About an ounce of Clyde Tombaugh's ashes are aboard the spacecraft, to commemorate his discovery of Pluto in 1930.
On its was to Pluto it fly by Jupiter with better cameras that was on Voyager.New Horizons used LORRI to take its first photographs of Jupiter on 4 September 2006 from a distance of 291 million kilometres (181 million miles). More detailed exploration of the system began in January 2007 with an infrared image of the moon Callisto as well as several black and white images of the planet itself. New Horizons received a Jupiter gravity assist with a closest approach on 28 February 2007 when it was 1.4 million miles) from the planet. The flyby increased New Horizons' speed by 9,000 miles per hour accelerating the probe 52,000 miles per hour relative to the Sun and shortening its voyage to Pluto by three years.
The flyby was the center of a 4-month intensive observation campaign lasting from January to June. Being an ever-changing scientific target, Jupiter was observed intermittently since the end of the Galileo mission. Knowledge about the planet benefited from the fact that New Horizons instruments were built using the latest technology, especially in the area of cameras, representing a significant improvement over Galileo's cameras, which were evolved versions of Voyager cameras which, in turn, were evolved Mariner cameras. The Jupiter encounter also served as a shakedown and dress rehearsal for the Pluto encounter. Because of the much shorter distance from Jupiter to Earth, the communications link can transmit multiple loadings of the memory buffer; thus the mission actually returned more data from the Jovian system than it is expected to transmit from Pluto.
One of the main goals during the Jupiter encounter was observing the planets atmospheric conditions and analyzing the structure and composition of its clouds. Heat induced lightning strikes in the polar regions and "waves" that indicate violent storm activity were observed and measured. The Little Red Spot, spanning up to 70% of Earth's diameter, was imaged from up close for the first time.
Observing from different angles and illumination conditions New Horizons took detailed images of Jupiter's faint ring system discovering debris left over from recent collisions within the rings or from some other unexplained phenomena. The search for undiscovered moons within the rings showed no results. Travelling through the planet's magnetosphere New Horizons collected valuable particle readings. "Bubbles" of plasma which are believed to be formed from material ejected by the moon Io were noticed in the magnetotail.
After passing bu Jupiter the space probe was place in Hibernation since there wasn't anything to see except Pluto which was many years away. Redundant components as well as guidance and control systems will be shut down in order to extend their life cycle, decrease operational costs and free the Deep Space Network for other missions. During hibernation mode, the onboard computer monitors the probe's systems and transmits a signal back to Earth: a "green" code if everything is functioning as expected or a "red" code if the mission control's assistance is needed. The probe will be activated for about two months a year so that the instruments can be calibrated and the systems checked. New Horizons first hibernation mode cycle started on 28 June 2007.
After astronomers announced the discovery of two new moons in the Pluto system, Kerberos and Styx, mission planners started contemplating the possibility of the probe running into unseen debris and dust left over from earlier collisions with the moons. A study based on 18 months of computer simulations, Earth-based telescope observations and occultations of the Pluto system revealed that the possibility of a catastrophic collision with debris or dust is less than 0.3% if the probe is to continue on its present course. If the hazard increases, New Horizons will utilize one of two possible contingency plans, the so-called SHBOTs (Safe Haven by Other Trajectories): the probe could continue on its present trajectory with the antenna facing the incoming particles so the more vital systems would be protected, or, it could position its antenna and make a course correction that would take it just 3000 km from the surface of Pluto where it's expected that the atmospheric drag cleaned the surrounding space of possible debris.
The spacecraft carries seven scientific instruments. Total mass is 31 kg (68 lb) and rated power is 21 watts (though not all instruments operate simultaneously).
Fundamental physics-Pioneer Anomaly
It was shown that New Horizons may be used to test the Pioneer Anomaly issue.
Long Range Reconnaissance Imager (LORRI)
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), for one of the largest silicon-carbide telescopes yet flown
Pluto Exploration Remote Sensing Investigation (PERSI)
This consists of two instruments: The Ralph telescope, 6 cm (2.4 in) in aperture, with 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. The second instrument is an ultraviolet imaging spectrometer, Alice. Alice resolves 1,024 wavelength bands in the far and extreme ultraviolet (from 50–180 nm), over 32 view fields. Its goal is to view the atmospheric makeup of Pluto. This Alice is derived from an Alice on the Rosetta mission. Ralph, designed afterwards, was named after Alice's husband on The Honeymooners. Ralph and Alice are names, not acronyms.
Plasma and high energy particle spectrometer suite (PAM)
PAM consists of two instruments: SWAP (Solar Wind At Pluto), a toroidal electrostatic analyzer and retarding potential analyzer, and PEPSSI (Pluto Energetic Particle Spectrometer Science Investigation), a time of flight ion and electron sensor. SWAP measures particles of up to 6.5 keV, PEPSSI goes up to 1 MeV. Because of the tenuous solar wind at Pluto's distance, the SWAP instrument has the largest aperture of any such instrument ever flown.
Radio Science Experiment (REX)
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.
Venetia Burney Student Dust Counter (VBSDC)
Built by students at the University of Colorado at Boulder, the Student Dust Counter will operate continuously through the trajectory to make dust measurements. It consists of a detector panel, about 18 by 12 inches (460 mm × 300 mm), 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 shall 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 earthlike planets can be found in our universe. The dust counter is named for Venetia Burney, who first suggested the name "Pluto" at the age of 11. An interesting thirteen-minute short film about VBSDC garnered an Emmy award for student achievement in 2006
The main Flyby 2015!
Observations of Pluto, with the onboard LORRI imager plus Ralph telescope, will begin about 6 months prior to closest approach. The targets will be only a few pixels across. 70 days out, resolution will exceed the Hubble Space Telescope's resolution, lasting another two weeks after the flyby. This should detect any rings or any additional moons (eventually down to 2 km diameter), for avoidance and targeting maneuvers, and observation scheduling. Long-range imaging will include 40 km (25 mi) mapping of Pluto and Charon 3.2 days out. This is half the rotation period of Pluto–Charon and will allow imaging of the side of both bodies that will be facing away from the spacecraft at closest approach. Coverage will repeat twice per day, to search for changes due to snows or cryovolcanism. Still, due to Pluto's tilt and rotation, a portion of the northern hemisphere will be in shadow at all times.
During the flyby, LORRI should be able to obtain select images with resolution as high as 50 m/px (if closest distance is around 10,000 km), and MVIC should obtain 4-color global dayside maps at 1.6 km resolution. LORRI and MVIC will attempt to overlap their respective coverage areas to form stereo pairs. LEISA will obtain hyperspectral near-infrared maps at 7 km/px globally and 0.6 km/pixel for selected areas. Meanwhile, Alice will characterize the atmosphere, both by emissions of atmospheric molecules (airglow), and by dimming of background stars as they pass behind Pluto (occultation).
During and after closest approach, SWAP and PEPSSI will sample the high atmosphere and its effects on the solar wind. VBSDC will search for dust, inferring meteoroid collision rates and any invisible rings. REX will perform active and passive radio science. Ground stations on Earth will transmit a powerful radio signal as New Horizons passes behind Pluto's disk, then emerges on the other side. The communications dish will measure the disappearance and reappearance of the radio occultation signal. The results will resolve Pluto's diameter (by their timing) and atmospheric density and composition (by their weakening and strengthening pattern). (Alice can perform similar occultations, using sunlight instead of radio beacons.) Previous missions had the spacecraft transmit through the atmosphere, to Earth ("downlink"). Low power and extreme distance means New Horizons will be the first such "uplink" mission. Pluto's mass and mass distribution will be evaluated by their tug on the spacecraft. As the spacecraft speeds up and slows down, the radio signal will experience a Doppler shift. The Doppler shift will be measured by comparison with the ultrastable oscillator in the communications electronics.
Reflected sunlight from Charon will allow some imaging observations of the nightside. Backlighting by the Sun will highlight any rings or atmospheric hazes. REX will perform radiometry of the nightside.
Initial, highly-compressed images will be transmitted within days. The science team will select the best images for public release. Uncompressed images will take about nine months[citation needed] to transmit, depending on Deep Space Network traffic. It may turn out, however, that fewer months will be needed. The spacecraft link is proving stronger than expected, and it is possible that both downlink channels may be ganged together to nearly double the data rate.
To bad its just a flyby but a orbiter would take to long to get there,they was dealing with nature.Pluto was moving away from the Sun this means that there would be no atmosphere to study if a orbiter was send plus with a travel time of about 38 years. During Pluto lifetime ,it lost up to 14 feet of it surface during these close approaches to the Sun.AT time Pluto get closer to the Sun than Neptune( here its distance from our sun-4.4–7.4 billion km) Pluto act more like a comet than a planet. They think during the formation of our solar system that Neptune and Uranus form between Jupiter ans Saturn and when Neptune and Uranus shift their position with in the solar system to their current position they send many Pluto size object toward the inner solar system and since they thing these pluto and Kuiper belt objects are made out of 80%water this give the Earth,Venus,Mars, Mercury with large amount of water. Mercury water was gone in no time and Venus,Mars during this time to the current time lost their water (Most of it for Mars and all of it for Venus) Earth was the only one that keep all of time!
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