New Horizons Research Paper
New Horizons
TABLE OF CONTENTS
Introduction
Missions beyond Mars
Design challenges for long missions
Electrical power
Launch
Jupiter gravity assist
Zipping by Jupiter
Plans for Pluto
Beyond Pluto
Exploring the Kuiper Belt
Current Status
Introduction
New Horizons is a NASA New Frontiers mission managed by the Johns Hopkins University Applied Physics Laboratory. Launched on January 19, 2006, the New Horizons spacecraft is due to pass Jupiter on February 28, 2007, en route to photographing and examining Pluto and other objects in the Kuiper Belt. Currently traveling at over 51,000 miles per hour, New Horizons was the fastest spacecraft ever launched. Yet, it will require eight more years to reach planet Pluto, which will …show more content…
be more than 3 billion miles away from the Sun when New Horizons arrives. After its Pluto-system encounter, New Horizons will continue on to explore the Kuiper Belt, then escape the solar system and fly into interstellar space.
The first spacecraft to explore Pluto and its system of moons, New Horizons may also be the last for a while. As Pluto moves away from the Sun, its atmosphere will freeze and condense on its surface, making photography and other measurements difficult. Pluto will not be as close to the Sun as it is now for nearly another 250 years. New Horizons is carrying a compact disc with the names of more than 430,000 people from around the world who are interested in the project, the first-ever planetary flight experiment developed by undergraduate students, and the ashes of Clyde Tombaugh, who discovered Pluto in 1930.
In November 2001, the Johns Hopkins Applied Physics Laboratory took on this task, to build a planetary observatory named New Horizons, bound for Pluto. APL has delivered the spacecraft to Cape Canaveral, Florida, for launch in January 2006. If the mission fully succeeds, in July 2015 New Horizons will fly past Pluto for the first reconnaissance of that strange little ball of ice and rock, snapping pictures, mapping its terrain, analyzing its atmosphere, and sampling space dust and the solar wind. For nine months after it will transmit data back to Earth as it races toward an even more distant region of the solar system known as the Kuiper Belt, where scientists hope to extend its mission.
Missions beyond Mars
Exploration of the outer planets requires extreme patience.
Our launch vehicles are no powerful enough to send massive spacecraft directly to the giant planets, so they must take circuitous paths returning to Earth or even traveling inward to Venus for gravity assists to boost momentum enough to send them beyond the asteroid belt. Rendezvousing with asteroids and comets can be even more challenging; they lack sufficient mass to brake fast-moving spacecraft into orbit, so the ships must perform years of orbit adjustment to match position and velocity with the tiniest worlds.
Power is also a problem. Located very far from the Sun, comets, outer planets, and most asteroids receive very little solar energy. Solar arrays must be very large to gather the little sunlight, like those of Rosetta, Dawn, and Juno; or else spacecraft must carry radioisotope thermoelectric generators. The successes of missions like Voyager, Pioneer, Galileo, Cassini-Huygens, and New Horizons require these nuclear power supplies, but Earth has run short of refined plutonium-238, preventing us from planning future …show more content…
missions.
New Horizons is the result of a long battle to take advantage of a once-in-a-lifetime opportunity for a Jupiter gravity assist trajectory to Pluto. It observed Jupiter over five months around the flyby in early 2007, with its closest approach on February 27. It was the first spacecraft to observe the newly formed Little Red Spot, and also caught Io's north polar volcano Tvashtar in the middle of a spectacular eruption. It will travel within 10,000 kilometers of Pluto before traveling onward to a second (and probably much more distant) encouter with a much smaller Kuiper belt object.
Design challenges for long missions
Spacecraft typically have a set design lifetime, similar to warranties on electronics or cars. Over time, solar particles, cosmic rays and other phenomena can degrade the surface of the spacecraft or mess up the electronics. This makes long missions such as New Horizons especially challenging.
"You've got to remember that it takes 9.5 years to even get to where we want to take the mission," said Glen Fountain, the New Horizons mission project manager from Johns Hopkins University Applied Physics Laboratory, in a 2006 interview with NASA.
Mission planners planned to keep the spacecraft in deep hibernation after a quick pass by Jupiter in February 2007. Essential systems will be turned on, but the rest will stay quiet until the spacecraft gets close to Pluto.
NASA does a detailed systems check of the spacecraft once a year to make sure it's working properly and to, if necessary, make adjustments to its path to Pluto. The spacecraft also ferries a basic signal back to Earth once a week.
Electrical power
The spacecraft has a nuclear power supply to generate electricity over its many years of life.
Plutonium-238 fuel is used to power a radioisotope thermal generator (RTG), which is the probe's long-life battery. An RTG converts heat from naturally decaying plutonium into electricity.
The RTG uses plutonium dioxide ceramic pellets as a heat source and solid-state thermocouples that convert the plutonium's heat energy to electricity.
Half of the plutonium for New Horizons was on hand when the U.S. Department of Energy (DoE) stopped work at the nuclear weapons plant in July 2004. A total of 36 of the 72 fuel units ordered had been left over from a spare RTG built earlier for NASA's Galileo and Cassini missions. When the lab shut down, it had 18 more units in the works. The launch went ahead with as few as 61 fuel units.
More plutonium dioxide ceramic could be made at Los Alamos scientists by converting plutonium bought from Russia into pellets packaged in hockey-puck-sized containers. The Argonne National Laboratory at Idaho Falls could put the pellet containers into an RTG.
An RTG with a full load of 72 fuel units can deliver 200 watts of electricity. With only half of its fuel, 36 fuel units, it could deliver about 100 watts. With 61 fuel units, the RTG could provide 170 watts of electrical power. Such a quantity of electricity could power seven science instruments and spacecraft systems aboard New Horizons.
Launch
The launch of New Horizons was originally scheduled for January 11, 2006, but was initially delayed until January 17 to allow for bore scope inspections of the Atlas rocket's kerosene tank. Further delays related to low cloud ceiling conditions downrange, and high winds and technical difficulties — unrelated to the rocket itself — prevented launch for a further two days. The probe finally lifted off from Pad 41 at Cape Canaveral Air Force Station, Florida, directly south of Space Shuttle Launch Complex 39, at 14:00 EST on January 19, 2006.
Space Launch Complex 41 during New Horizons launch
The Centaur second stage reignited at 14:30 EST (19:30 UTC), successfully sending the probe on a solar-escape trajectory. New Horizons took only nine hours to reach the Moon's orbit, passing lunar orbit before midnight EST that day.
Although there were backup launch opportunities in February 2006 and February 2007, only the first 23 days of the 2006 window permitted the Jupiter fly-by. Any launch outside that period would have forced the spacecraft to fly a slower trajectory directly to Pluto, delaying its encounter by 2–4 years.
The craft was launched by a Lockheed Martin Atlas V 551 rocket, with an ATK Star 48B third stage added to increase the heliocentric (escape) speed.
This was the first launch of the 551 configuration of the Atlas V, as well as the first Atlas V launch with an additional third stage (Atlas V rockets usually do not have a third stage). Previous flights had used none, two, or three solid boosters, but never five. This puts the Atlas V 551 take-off thrust, at well over 2,000,000 lb, past the Delta IV-Heavy. The major part of this thrust is supplied by the Russian RD-180 engine, providing 4.152 MN. The Delta IV-H remains the larger vehicle, at over 1,600,000 lb (726,000 kg) compared to 1,260,000 lb of the AV-010. The Atlas V rocket had earlier been slightly damaged when Hurricane Wilma swept across Florida on October 24, 2005. One of the solid rocket boosters was hit by a door. The booster was replaced with an identical unit, rather than inspecting and prequalifying the
original.
New Horizons probe launched from Cape Canaveral on January 19, 2006
The Star 48B third stage is also on a hyperbolic Solar System escape trajectory, and reached Jupiter before the New Horizons spacecraft. However, since it is not in controlled flight, it did not receive the correct gravity assist, and will only pass within 120,000,000 miles of Pluto.
New Horizons is often erroneously given the title of Fastest Spacecraft Ever Launched, when in fact the Helios probes are the holders of that title. New Horizons achieved the highest launch velocity and thus left Earth faster than any other spacecraft to date. It is also the first spacecraft launched directly into a solar escape trajectory, which requires an approximate velocity of 36,900 mph, plus losses, all to be provided by the launcher. However, it will not be the fastest spacecraft to leave the Solar System. This record is held by Voyager 1, currently travelling at 38,400 mph relative to the Sun. Voyager 1 attained greater hyperbolic excess velocity from Jupiter and Saturn gravitational slingshots than New Horizons. Other spacecraft, such as Helios 1 & 2, can also be measured as the fastest objects, due to their orbital velocity relative to the Sun at perihelion. However, because they remain in solar orbit, their orbital energy relative to the Sun is lower than the five probes, and three other third stages on hyperbolic trajectories, including New Horizons, that achieved solar escape velocity, as the Sun has a much deeper gravitational well than Earth.
Jupiter gravity assist
New Horizons at periapsis with Jupiter on February 28, 2007
New Horizons' Long Range Reconnaissance Imager (LORRI) took its first photographs of Jupiter on September 4, 2006. The spacecraft began further study of the Jovian system in December 2006.
New Horizons received a Jupiter gravity assist with a closest approach at 5:43:40 UTC (12:43:40am EST) on February 28, 2007. It passed through the Jupiter system at 47,000 mph. The flyby increased New Horizons' speed away from the Sun by nearly 8,900 mph, putting the spacecraft on a faster trajectory to Pluto, about 2.5 degrees out of the plane of the Earth's orbit. As of November 2009, the Sun’s gravity has slowed the spacecraft to about 37,260 mph. New Horizons was the first probe launched directly toward Jupiter since the Ulysses probe in 1990.
While at Jupiter, New Horizons' instruments made refined measurements of the orbits of Jupiter's inner moons, particularly Amalthea. The probe's cameras measured volcanoes on Io and studied all four Galilean moons in detail, as well as long-distance studies of the outer moons Himalia and Elara. Imaging of the Jovian system began on September 4, 2006. The craft also studied Jupiter's Little Red Spot and the planet's magnetosphere and tenuous ring system.
Zipping by Jupiter
New Horizons launched Jan. 19, 2006, on an Atlas V rocket from Cape Canaveral Air Force Station in Florida. A power outage and high winds delayed two previous launch attempts, but New Horizons made it safely into space on the third try. This montage of New Horizons images shows Jupiter and its volcanic moon Io, and was taken during the spacecraft's Jupiter flyby in early 2007. The spacecraft's first destination was Jupiter, in February and March 2007. New Horizons passed by less than 1.4 million miles (2.4 million km) of the solar system's largest planet, making it the first spacecraft to swing by since the finished its mission at Jupiter in 2003. Among New Horizons' first pictures was some of Io – Jupiter's volcanic moon. The spacecraft captured the clearest pictures ever of the Tvashtar volcano on Io, showing volcanic fallout that was bigger than the state of Texas. Additionally, the spacecraft flew through a stream of charged particles swirling behind Jupiter. It found large bubbles of charged particles, or plasma, and also revealed variations in the stream. At the time, astronomers said the observations could help with understanding the environment around "hot Jupiter" planets found at other stars.
One of the principal aims of New Horizons is to figure out the origins of Pluto and its companion Charon – a moon that is more than half Pluto's size. At the time, Pluto and Charon were considered a double planet. NASA believed Charon formed when Pluto hit another big object long ago, creating debris that circled around Pluto and eventually formed Charon. It's a similar theory to how Earth's moon formed, so the scientists hoped to understand the creation of our moon better by looking at Charon's origins. Scientists are also eager to learn about the visual differences between Charon and Pluto. From Hubble observations, researchers deduced Pluto is far more reflective than Charon, and that Pluto has an atmosphere while Charon does not. NASA further speculated that Pluto might even have volcanic activity, because the Voyager 2 spacecraft spotted possible volcanoes on Triton, a moon of Neptune that is of a similar size and composition. However, no one will know for sure until New Horizons gets close enough to give Pluto its close-up. NASA is already preparing for that time. During one of its periodic check-ins on New Horizons in 2012, NASA did simulated Pluto observations to see if its plans were in tip-top shape. Although New Horizons was still 850 million miles away from its target, NASA practiced the essential things the spacecraft will have to do when it is near Pluto. The agency sent messages back and forth to the spacecraft, and briefly turned on Pluto's instruments and cameras to collect data. Indications immediately after the test showed that New Horizons was performing as expected, the agency said.
Plans for Pluto
One of the principal aims of New Horizons is to figure out the origins of Pluto and its companion Charon – a moon that is more than half Pluto's size. At the time, Pluto and Charon were considered a double planet. NASA believed Charon formed when Pluto hit another big object long ago, creating debris that circled around Pluto and eventually formed Charon. It's a similar theory to how Earth's moon formed, so the scientists hoped to understand the creation of our moon better by looking at Charon's origins. Scientists are also eager to learn about the visual differences between Charon and Pluto. From Hubble observations, researchers deduced Pluto is far more reflective than Charon, and that Pluto has an atmosphere while Charon does not. NASA further speculated that Pluto might even have volcanic activity, because the Voyager 2 spacecraft spotted possible volcanoes on Triton, a moon of Neptune that is of a similar size and composition. However, no one will know for sure until New Horizons gets close enough to give Pluto its close-up. NASA is already preparing for that time. During one of its periodic check-ins on New Horizons in 2012, NASA did simulated Pluto observations to see if its plans were in tip-top shape. Although New Horizons was still 850 million miles away from its target, NASA practiced the essential things the spacecraft will have to do when it is near Pluto. The agency sent messages back and forth to the spacecraft, and briefly turned on Pluto's instruments and cameras to collect data. Indications immediately after the test showed that New Horizons was performing as expected, the agency said.
Beyond Pluto
However, in 2013 or 2014, we plan to propose to NASA that we carry out further explorations after Pluto. If NASA approves that, New Horizons will explore one or two ancient Kuiper Belt Objects (KBOs). We are currently in the midst of an extensive search to find suitable KBOs that are within reach of our expected post-Pluto fuel supply.
Based on that predicted fuel supply, we estimate that will likely be able to choose between several reachable KBOs if our searches are successful. This is a tough search, for two reasons. First, the only KBOs within our reach are likely to be small, roughly 50 kilometers in diameter. Because they are small and far away, they will be faint as seen from Earth. In fact, calculations show that the KBOs we need to find are going to be about 25,000 times fainter than Pluto, which is itself about 10,000 times fainter than the eye can see. This means we have to search for objects with the largest telescopes and most sensitive astronomical cameras on Earth.
The second factor making the search tough is that our trajectory is pointed at the heart of the Milky Way's densest star fields - those of the galactic center in the constellation Sagittarius. So our search is kind of a "needle in a haystack" hunt for very faint objects slowly moving against regions of the sky thick with stars!
We began our KBO search last year and have been using telescopes like the giant Keck, Gemini, Subaru and Magellan observatories. So far those searches have discovered about two-dozen faint KBOs in those dense star fields.
Unfortunately, none of the KBOs found so far are close enough to be within reach of our fuel supply. However, computer model predictions indicate that with one or two more years of such a search, we should be able to find at least one, and more likely several reachable KBOs. After we find them, we'll study those flyby candidates to compare them against one another for their brightness, colors, rotation periods and orbits, and to see if any have obvious moons.
Then, in 2015 - assuming NASA approves our extended mission as we hope - we'll select our actual flyby target. Once we choose the first target, we'll plan the engine burn - most likely in September or October of 2015 - that retargets our trajectory toward that soon-to-be explored KBO. Calculations show that it will most likely take three or four years - and perhaps even a bit longer - to reach our first KBO. So based on the most likely scenario, we expect a flyby in 2018 or 2019, though it could be as early as 2016 or as late as 2021.
Exploring the Kuiper Belt
Currently, New Horizons is healthy and isn't using any of its backup systems, and New Horizons has the power and technical capabilities fly late into the 2020s or even into the 2030s if its health remains good. Moreover, all of our scientific instruments and our onboard spacecraft system were designed to work even at the far edge of the main Kuiper Belt, which we'll reach in about 2021. So there aren't any technical obstacles to KBO flybys once we find good targets.
Along the way to our close-up KBO flyby or flybys, we will be using New Horizons to study the environment of the Kuiper Belt. Of most importance will be studies of the dust particle distribution created by KBO collisions as well as the composition and density of the solar wind and hemispheric hydrogen in this distant region. We also expect to make distant flybys of several KBOs to search for satellites they may have. From that range New Horizons can search for KBO satellites more sensitively than any ground-based telescope or the Hubble Space Telescope.
We plan to fly past any target KBO at about 10,000-25,000 kilometers - as close or perhaps twice as far as we'll fly past Pluto. So the images of these KBOs - ancient building blocks of the planets - should be similarly detailed to our imagery of Pluto and its moons.
Current Status
Pluto is found in the Kuiper Belt, the ring of icy objects beyond Neptune's orbit. As of today, New Horizons has put about 2.14 billion miles (3.45 billion km) on its odometer, with roughly another 1 billion miles (1.6 billion km) left to go before the close encounter.
The probe's work won't be done after it flies by the Pluto system in 2015. The mission team wants New Horizons to study one or two other Kuiper Belt objects as well.
NASA has billed New Horizons as the fastest spacecraft ever launched from Earth. According to the mission team, the probe is now speeding through space at 34,426 mph (55,404 kph) relative to the sun.
While New Horizons spends most of its cruise time hibernating, it's awake for now. Scientists and engineers are performing various tests on the spacecraft throughout January, Stern said, adding that the spacecraft is in good health.
References
New Horizons Mission to Pluto www.windows2universe.org http://www.windows2universe.org/space_missions/robotic/pluto_new_horizon/new_horizons_pluto.html
[0709.4417] The New Horizons Pluto Kuiper belt Mission: An Overview with Historical Context arxiv.org http://arxiv.org/abs/0709.4417
http://www.boulder.swri.edu/~tcase/Ottman-Hersman_IECEC_paper.pdf www.boulder.swri.edu http://pluto.jhuapl.edu/
SciTechTalk: NASA's planetary playbook www.upi.com http://www.upi.com/Science_News/Technology/2012/09/30/SciTechTalk-NASAs-planetary-playbook/UPI-74581349001060/
Beyond planet Earth www.tctimes.com http://www.tctimes.com/living/beyond-planet-earth/article_f5fb5f88-07e0-11e2-8d58-0019bb2963f4.html
TABLE OF CONTENTS
Introduction
Missions beyond Mars
Design challenges for long missions
Electrical power
Launch
Jupiter gravity assist
Zipping by Jupiter
Plans for Pluto
Beyond Pluto
Exploring the Kuiper Belt
Current Status
Introduction
New Horizons is a NASA New Frontiers mission managed by the Johns Hopkins University Applied Physics Laboratory. Launched on January 19, 2006, the New Horizons spacecraft is due to pass Jupiter on February 28, 2007, en route to photographing and examining Pluto and other objects in the Kuiper Belt. Currently traveling at over 51,000 miles per hour, New Horizons was the fastest spacecraft ever launched. Yet, it will require eight more years to reach planet Pluto, which will …show more content…
be more than 3 billion miles away from the Sun when New Horizons arrives. After its Pluto-system encounter, New Horizons will continue on to explore the Kuiper Belt, then escape the solar system and fly into interstellar space.
The first spacecraft to explore Pluto and its system of moons, New Horizons may also be the last for a while. As Pluto moves away from the Sun, its atmosphere will freeze and condense on its surface, making photography and other measurements difficult. Pluto will not be as close to the Sun as it is now for nearly another 250 years. New Horizons is carrying a compact disc with the names of more than 430,000 people from around the world who are interested in the project, the first-ever planetary flight experiment developed by undergraduate students, and the ashes of Clyde Tombaugh, who discovered Pluto in 1930.
In November 2001, the Johns Hopkins Applied Physics Laboratory took on this task, to build a planetary observatory named New Horizons, bound for Pluto. APL has delivered the spacecraft to Cape Canaveral, Florida, for launch in January 2006. If the mission fully succeeds, in July 2015 New Horizons will fly past Pluto for the first reconnaissance of that strange little ball of ice and rock, snapping pictures, mapping its terrain, analyzing its atmosphere, and sampling space dust and the solar wind. For nine months after it will transmit data back to Earth as it races toward an even more distant region of the solar system known as the Kuiper Belt, where scientists hope to extend its mission.
Missions beyond Mars
Exploration of the outer planets requires extreme patience.
Our launch vehicles are no powerful enough to send massive spacecraft directly to the giant planets, so they must take circuitous paths returning to Earth or even traveling inward to Venus for gravity assists to boost momentum enough to send them beyond the asteroid belt. Rendezvousing with asteroids and comets can be even more challenging; they lack sufficient mass to brake fast-moving spacecraft into orbit, so the ships must perform years of orbit adjustment to match position and velocity with the tiniest worlds.
Power is also a problem. Located very far from the Sun, comets, outer planets, and most asteroids receive very little solar energy. Solar arrays must be very large to gather the little sunlight, like those of Rosetta, Dawn, and Juno; or else spacecraft must carry radioisotope thermoelectric generators. The successes of missions like Voyager, Pioneer, Galileo, Cassini-Huygens, and New Horizons require these nuclear power supplies, but Earth has run short of refined plutonium-238, preventing us from planning future …show more content…
missions.
New Horizons is the result of a long battle to take advantage of a once-in-a-lifetime opportunity for a Jupiter gravity assist trajectory to Pluto. It observed Jupiter over five months around the flyby in early 2007, with its closest approach on February 27. It was the first spacecraft to observe the newly formed Little Red Spot, and also caught Io's north polar volcano Tvashtar in the middle of a spectacular eruption. It will travel within 10,000 kilometers of Pluto before traveling onward to a second (and probably much more distant) encouter with a much smaller Kuiper belt object.
Design challenges for long missions
Spacecraft typically have a set design lifetime, similar to warranties on electronics or cars. Over time, solar particles, cosmic rays and other phenomena can degrade the surface of the spacecraft or mess up the electronics. This makes long missions such as New Horizons especially challenging.
"You've got to remember that it takes 9.5 years to even get to where we want to take the mission," said Glen Fountain, the New Horizons mission project manager from Johns Hopkins University Applied Physics Laboratory, in a 2006 interview with NASA.
Mission planners planned to keep the spacecraft in deep hibernation after a quick pass by Jupiter in February 2007. Essential systems will be turned on, but the rest will stay quiet until the spacecraft gets close to Pluto.
NASA does a detailed systems check of the spacecraft once a year to make sure it's working properly and to, if necessary, make adjustments to its path to Pluto. The spacecraft also ferries a basic signal back to Earth once a week.
Electrical power
The spacecraft has a nuclear power supply to generate electricity over its many years of life.
Plutonium-238 fuel is used to power a radioisotope thermal generator (RTG), which is the probe's long-life battery. An RTG converts heat from naturally decaying plutonium into electricity.
The RTG uses plutonium dioxide ceramic pellets as a heat source and solid-state thermocouples that convert the plutonium's heat energy to electricity.
Half of the plutonium for New Horizons was on hand when the U.S. Department of Energy (DoE) stopped work at the nuclear weapons plant in July 2004. A total of 36 of the 72 fuel units ordered had been left over from a spare RTG built earlier for NASA's Galileo and Cassini missions. When the lab shut down, it had 18 more units in the works. The launch went ahead with as few as 61 fuel units.
More plutonium dioxide ceramic could be made at Los Alamos scientists by converting plutonium bought from Russia into pellets packaged in hockey-puck-sized containers. The Argonne National Laboratory at Idaho Falls could put the pellet containers into an RTG.
An RTG with a full load of 72 fuel units can deliver 200 watts of electricity. With only half of its fuel, 36 fuel units, it could deliver about 100 watts. With 61 fuel units, the RTG could provide 170 watts of electrical power. Such a quantity of electricity could power seven science instruments and spacecraft systems aboard New Horizons.
Launch
The launch of New Horizons was originally scheduled for January 11, 2006, but was initially delayed until January 17 to allow for bore scope inspections of the Atlas rocket's kerosene tank. Further delays related to low cloud ceiling conditions downrange, and high winds and technical difficulties — unrelated to the rocket itself — prevented launch for a further two days. The probe finally lifted off from Pad 41 at Cape Canaveral Air Force Station, Florida, directly south of Space Shuttle Launch Complex 39, at 14:00 EST on January 19, 2006.
Space Launch Complex 41 during New Horizons launch
The Centaur second stage reignited at 14:30 EST (19:30 UTC), successfully sending the probe on a solar-escape trajectory. New Horizons took only nine hours to reach the Moon's orbit, passing lunar orbit before midnight EST that day.
Although there were backup launch opportunities in February 2006 and February 2007, only the first 23 days of the 2006 window permitted the Jupiter fly-by. Any launch outside that period would have forced the spacecraft to fly a slower trajectory directly to Pluto, delaying its encounter by 2–4 years.
The craft was launched by a Lockheed Martin Atlas V 551 rocket, with an ATK Star 48B third stage added to increase the heliocentric (escape) speed.
This was the first launch of the 551 configuration of the Atlas V, as well as the first Atlas V launch with an additional third stage (Atlas V rockets usually do not have a third stage). Previous flights had used none, two, or three solid boosters, but never five. This puts the Atlas V 551 take-off thrust, at well over 2,000,000 lb, past the Delta IV-Heavy. The major part of this thrust is supplied by the Russian RD-180 engine, providing 4.152 MN. The Delta IV-H remains the larger vehicle, at over 1,600,000 lb (726,000 kg) compared to 1,260,000 lb of the AV-010. The Atlas V rocket had earlier been slightly damaged when Hurricane Wilma swept across Florida on October 24, 2005. One of the solid rocket boosters was hit by a door. The booster was replaced with an identical unit, rather than inspecting and prequalifying the
original.
New Horizons probe launched from Cape Canaveral on January 19, 2006
The Star 48B third stage is also on a hyperbolic Solar System escape trajectory, and reached Jupiter before the New Horizons spacecraft. However, since it is not in controlled flight, it did not receive the correct gravity assist, and will only pass within 120,000,000 miles of Pluto.
New Horizons is often erroneously given the title of Fastest Spacecraft Ever Launched, when in fact the Helios probes are the holders of that title. New Horizons achieved the highest launch velocity and thus left Earth faster than any other spacecraft to date. It is also the first spacecraft launched directly into a solar escape trajectory, which requires an approximate velocity of 36,900 mph, plus losses, all to be provided by the launcher. However, it will not be the fastest spacecraft to leave the Solar System. This record is held by Voyager 1, currently travelling at 38,400 mph relative to the Sun. Voyager 1 attained greater hyperbolic excess velocity from Jupiter and Saturn gravitational slingshots than New Horizons. Other spacecraft, such as Helios 1 & 2, can also be measured as the fastest objects, due to their orbital velocity relative to the Sun at perihelion. However, because they remain in solar orbit, their orbital energy relative to the Sun is lower than the five probes, and three other third stages on hyperbolic trajectories, including New Horizons, that achieved solar escape velocity, as the Sun has a much deeper gravitational well than Earth.
Jupiter gravity assist
New Horizons at periapsis with Jupiter on February 28, 2007
New Horizons' Long Range Reconnaissance Imager (LORRI) took its first photographs of Jupiter on September 4, 2006. The spacecraft began further study of the Jovian system in December 2006.
New Horizons received a Jupiter gravity assist with a closest approach at 5:43:40 UTC (12:43:40am EST) on February 28, 2007. It passed through the Jupiter system at 47,000 mph. The flyby increased New Horizons' speed away from the Sun by nearly 8,900 mph, putting the spacecraft on a faster trajectory to Pluto, about 2.5 degrees out of the plane of the Earth's orbit. As of November 2009, the Sun’s gravity has slowed the spacecraft to about 37,260 mph. New Horizons was the first probe launched directly toward Jupiter since the Ulysses probe in 1990.
While at Jupiter, New Horizons' instruments made refined measurements of the orbits of Jupiter's inner moons, particularly Amalthea. The probe's cameras measured volcanoes on Io and studied all four Galilean moons in detail, as well as long-distance studies of the outer moons Himalia and Elara. Imaging of the Jovian system began on September 4, 2006. The craft also studied Jupiter's Little Red Spot and the planet's magnetosphere and tenuous ring system.
Zipping by Jupiter
New Horizons launched Jan. 19, 2006, on an Atlas V rocket from Cape Canaveral Air Force Station in Florida. A power outage and high winds delayed two previous launch attempts, but New Horizons made it safely into space on the third try. This montage of New Horizons images shows Jupiter and its volcanic moon Io, and was taken during the spacecraft's Jupiter flyby in early 2007. The spacecraft's first destination was Jupiter, in February and March 2007. New Horizons passed by less than 1.4 million miles (2.4 million km) of the solar system's largest planet, making it the first spacecraft to swing by since the finished its mission at Jupiter in 2003. Among New Horizons' first pictures was some of Io – Jupiter's volcanic moon. The spacecraft captured the clearest pictures ever of the Tvashtar volcano on Io, showing volcanic fallout that was bigger than the state of Texas. Additionally, the spacecraft flew through a stream of charged particles swirling behind Jupiter. It found large bubbles of charged particles, or plasma, and also revealed variations in the stream. At the time, astronomers said the observations could help with understanding the environment around "hot Jupiter" planets found at other stars.
One of the principal aims of New Horizons is to figure out the origins of Pluto and its companion Charon – a moon that is more than half Pluto's size. At the time, Pluto and Charon were considered a double planet. NASA believed Charon formed when Pluto hit another big object long ago, creating debris that circled around Pluto and eventually formed Charon. It's a similar theory to how Earth's moon formed, so the scientists hoped to understand the creation of our moon better by looking at Charon's origins. Scientists are also eager to learn about the visual differences between Charon and Pluto. From Hubble observations, researchers deduced Pluto is far more reflective than Charon, and that Pluto has an atmosphere while Charon does not. NASA further speculated that Pluto might even have volcanic activity, because the Voyager 2 spacecraft spotted possible volcanoes on Triton, a moon of Neptune that is of a similar size and composition. However, no one will know for sure until New Horizons gets close enough to give Pluto its close-up. NASA is already preparing for that time. During one of its periodic check-ins on New Horizons in 2012, NASA did simulated Pluto observations to see if its plans were in tip-top shape. Although New Horizons was still 850 million miles away from its target, NASA practiced the essential things the spacecraft will have to do when it is near Pluto. The agency sent messages back and forth to the spacecraft, and briefly turned on Pluto's instruments and cameras to collect data. Indications immediately after the test showed that New Horizons was performing as expected, the agency said.
Plans for Pluto
One of the principal aims of New Horizons is to figure out the origins of Pluto and its companion Charon – a moon that is more than half Pluto's size. At the time, Pluto and Charon were considered a double planet. NASA believed Charon formed when Pluto hit another big object long ago, creating debris that circled around Pluto and eventually formed Charon. It's a similar theory to how Earth's moon formed, so the scientists hoped to understand the creation of our moon better by looking at Charon's origins. Scientists are also eager to learn about the visual differences between Charon and Pluto. From Hubble observations, researchers deduced Pluto is far more reflective than Charon, and that Pluto has an atmosphere while Charon does not. NASA further speculated that Pluto might even have volcanic activity, because the Voyager 2 spacecraft spotted possible volcanoes on Triton, a moon of Neptune that is of a similar size and composition. However, no one will know for sure until New Horizons gets close enough to give Pluto its close-up. NASA is already preparing for that time. During one of its periodic check-ins on New Horizons in 2012, NASA did simulated Pluto observations to see if its plans were in tip-top shape. Although New Horizons was still 850 million miles away from its target, NASA practiced the essential things the spacecraft will have to do when it is near Pluto. The agency sent messages back and forth to the spacecraft, and briefly turned on Pluto's instruments and cameras to collect data. Indications immediately after the test showed that New Horizons was performing as expected, the agency said.
Beyond Pluto
However, in 2013 or 2014, we plan to propose to NASA that we carry out further explorations after Pluto. If NASA approves that, New Horizons will explore one or two ancient Kuiper Belt Objects (KBOs). We are currently in the midst of an extensive search to find suitable KBOs that are within reach of our expected post-Pluto fuel supply.
Based on that predicted fuel supply, we estimate that will likely be able to choose between several reachable KBOs if our searches are successful. This is a tough search, for two reasons. First, the only KBOs within our reach are likely to be small, roughly 50 kilometers in diameter. Because they are small and far away, they will be faint as seen from Earth. In fact, calculations show that the KBOs we need to find are going to be about 25,000 times fainter than Pluto, which is itself about 10,000 times fainter than the eye can see. This means we have to search for objects with the largest telescopes and most sensitive astronomical cameras on Earth.
The second factor making the search tough is that our trajectory is pointed at the heart of the Milky Way's densest star fields - those of the galactic center in the constellation Sagittarius. So our search is kind of a "needle in a haystack" hunt for very faint objects slowly moving against regions of the sky thick with stars!
We began our KBO search last year and have been using telescopes like the giant Keck, Gemini, Subaru and Magellan observatories. So far those searches have discovered about two-dozen faint KBOs in those dense star fields.
Unfortunately, none of the KBOs found so far are close enough to be within reach of our fuel supply. However, computer model predictions indicate that with one or two more years of such a search, we should be able to find at least one, and more likely several reachable KBOs. After we find them, we'll study those flyby candidates to compare them against one another for their brightness, colors, rotation periods and orbits, and to see if any have obvious moons.
Then, in 2015 - assuming NASA approves our extended mission as we hope - we'll select our actual flyby target. Once we choose the first target, we'll plan the engine burn - most likely in September or October of 2015 - that retargets our trajectory toward that soon-to-be explored KBO. Calculations show that it will most likely take three or four years - and perhaps even a bit longer - to reach our first KBO. So based on the most likely scenario, we expect a flyby in 2018 or 2019, though it could be as early as 2016 or as late as 2021.
Exploring the Kuiper Belt
Currently, New Horizons is healthy and isn't using any of its backup systems, and New Horizons has the power and technical capabilities fly late into the 2020s or even into the 2030s if its health remains good. Moreover, all of our scientific instruments and our onboard spacecraft system were designed to work even at the far edge of the main Kuiper Belt, which we'll reach in about 2021. So there aren't any technical obstacles to KBO flybys once we find good targets.
Along the way to our close-up KBO flyby or flybys, we will be using New Horizons to study the environment of the Kuiper Belt. Of most importance will be studies of the dust particle distribution created by KBO collisions as well as the composition and density of the solar wind and hemispheric hydrogen in this distant region. We also expect to make distant flybys of several KBOs to search for satellites they may have. From that range New Horizons can search for KBO satellites more sensitively than any ground-based telescope or the Hubble Space Telescope.
We plan to fly past any target KBO at about 10,000-25,000 kilometers - as close or perhaps twice as far as we'll fly past Pluto. So the images of these KBOs - ancient building blocks of the planets - should be similarly detailed to our imagery of Pluto and its moons.
Current Status
Pluto is found in the Kuiper Belt, the ring of icy objects beyond Neptune's orbit. As of today, New Horizons has put about 2.14 billion miles (3.45 billion km) on its odometer, with roughly another 1 billion miles (1.6 billion km) left to go before the close encounter.
The probe's work won't be done after it flies by the Pluto system in 2015. The mission team wants New Horizons to study one or two other Kuiper Belt objects as well.
NASA has billed New Horizons as the fastest spacecraft ever launched from Earth. According to the mission team, the probe is now speeding through space at 34,426 mph (55,404 kph) relative to the sun.
While New Horizons spends most of its cruise time hibernating, it's awake for now. Scientists and engineers are performing various tests on the spacecraft throughout January, Stern said, adding that the spacecraft is in good health.
References
New Horizons Mission to Pluto www.windows2universe.org http://www.windows2universe.org/space_missions/robotic/pluto_new_horizon/new_horizons_pluto.html
[0709.4417] The New Horizons Pluto Kuiper belt Mission: An Overview with Historical Context arxiv.org http://arxiv.org/abs/0709.4417
http://www.boulder.swri.edu/~tcase/Ottman-Hersman_IECEC_paper.pdf www.boulder.swri.edu http://pluto.jhuapl.edu/
SciTechTalk: NASA's planetary playbook www.upi.com http://www.upi.com/Science_News/Technology/2012/09/30/SciTechTalk-NASAs-planetary-playbook/UPI-74581349001060/
Beyond planet Earth www.tctimes.com http://www.tctimes.com/living/beyond-planet-earth/article_f5fb5f88-07e0-11e2-8d58-0019bb2963f4.html