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Raumfahrt - NEW HORIZONS auf Kurs zu Pluto - Update-5

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4.06.2015

Pluto Monde in chaotischen Zustand

Illustration showing the scale and comparative brightness of Pluto’s small moons. The surface craters are for illustration only and do not represent real imaging data. Image credits: NASA/ESA/A. Feild (STScI) - See more at: http://sen.com/news/pluto-s-moons-in-chaotic-state#sthash.MEB1MKNp.dpuf

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NASA’s New Horizons spacecraft, which is heading toward a July flyby of the dwarf planet Pluto, will find a far weirder world than scientists imagined when the probe began its journey more than nine years ago. For example, Pluto’s four small outer moons—all discovered after intricate analysis of Hubble Space Telescope images—are chaotic, the result of constantly battling shifting gravitational forces of Pluto and its primary companion Charon, according to a study published this week in the journal Nature. Pluto and Charon orbit each other, the only binary pair in the Solar System. As a result of orbiting a binary system—and an uneven one at that, as Charon’s diameter is just over half as big as Pluto’s—the outer moons wobble, flip and turn in unpredictable ways. “This is called chaos,” lead researcher Mark Showalter, with the SETI Institute in Mountain View, Calif.,  told reporters on a conference call. “It’s a phenomenon that comes up in certain physical systems where they become fundamentally unpredictable. The analysis was done on the moons Nix and Hydra, but scientists believe the results are applicable to Kerberos and Styx as well. “You can never really know enough about the orientation of Nix at any given time to really predict what its going to do very far into the future,” Showalter said. “If you have real estate on the north pole, you might suddenly discover one day that you’re on the south pole of Nix instead,” he added. “The Sun might rise in the west and set in the east. The Sun might rise in the west and set in the north, for that matter.” Complicating an already complex orbital ballet are the moons’ non-spherical shapes, more like American footballs or rugby balls than round. Scientists believe the moons formed after a collision between Pluto and a similarly sized body early in the Solar System’s history. More details are expected when New Horizons zooms between Pluto and its outer moons on July 14. The spacecraft is expected to come as close as about 7,750 miles to the dwarf planet and about 17,900 miles to Charon. The study also found that Kerberos is surprisingly dark, a sharp contrast to its highly reflective sibling moons. Why Kerberos is so black is another mystery that New Horizons may help solve. “We have already learned that Pluto hosts a rich and complex dynamical environment, seemingly out of proportion to its diminutive size,” lead researchers Showalter and Douglas Hamilton, with the University of Maryland, write in the Nature paper.

Quelle: SEN

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Pluto’s moons move in synchrony
Gravity binds together three satellites of dwarf planet.
Pluto's moons are shown in a composite image from NASA's New Horizons spacecraft.
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Three of Pluto’s small moons are locked together in a mutual orbital dance, planetary scientists have found. The discovery provides important context for NASA’s New Horizons spacecraft, which is hunting for undiscovered moons as it hurtles towards a 14 July fly-by of the dwarf planet.
The finding is also a step towards understanding Pluto’s peculiar assortment of at least five moons. “This is telling us some piece of the story of how the system formed,” says Mark Showalter, a planetary scientist at the SETI Institute in Mountain View, California, and lead author of a paper appearing in the 4 June issue of Nature1. “We just don’t know what that piece is yet.”
Pluto’s biggest moon, Charon, weighs in at a hefty 11% of the mass of Pluto itself. It may have formed during a cosmic collision early in the Solar System's history, billions of years ago. Debris from that smash may have coalesced into the much smaller moons Styx, Nix, Kerberos and Hydra.
Now, researchers have found that the orbits of Styx, Nix and Hydra became gravitationally locked together at some point. “If you lived in the Pluto system and were sitting on Nix, you would see Hydra go around three times every time Styx goes around twice,” Showalter says. This pattern, known as a three-body resonance, remains stable over time. It is similar to the so-called Laplace resonance that links Jupiter's moons Io, Europa and Ganymede.
“If you know where Hydra and Nix are, you can determine where Styx is,” says Showalter. “It is a little piece of order in the system.” Styx is the smallest of the three moons, and was probably captured into a communal dance by the others.
Hide and seek
Working with Douglas Hamilton, a planetary astronomer at the University of Maryland in College Park, Showalter searched for the resonance by combing through Hubble Space Telescope observations of how the moons move over time. The researchers also found that Kerberos is much darker than either Nix or Hydra — suggesting that it could be made of a different material — and that Nix and Hydra rotate chaotically on their axes, the only moons known to do so other than Saturn’s moon Hyperion.
The work will help researchers to understand how the Pluto system came to be, says Marina Brozović, a planetary scientist at the Jet Propulsion Laboratory in Pasadena, California, who has hunted for resonances among Pluto’s moons2. “But off the top of my head, I do not see how a Laplace resonance between Styx, Nix and Hydra will shape the science results that come out of New Horizons,” she says.
New Horizons is less than 49 million kilometres from Pluto and closing in fast. It is now searching for small, faint moons that Hubble could not spot. None have been found so far, but unseen moons could be lurking in several places — including along the orbits of moons already known to exist.
Even smaller moons, less than 10% the mass of Styx, could also be lurking between Styx and Hydra, says Simon Porter, a planetary scientist at the Southwest Research Institute in Boulder, Colorado. Porter has been putting hypothetical moons of Pluto into orbital models and seeing which ones might be able to exist in real life3.
Showalter thinks that any new moons, if they exist, are likely to be small and orbiting farther out than Hydra, the outermost moon currently known. “But anything I say about Pluto right now could easily be obsolete by next week,” he says. “Or tomorrow.”
Quelle: nature
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Update: 12.06.2015
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NASA Announces Television Coverage, Media Activities for Pluto Flyby 

NASA is inviting media to cover New Horizons’ historic Pluto flyby in mid-July, including the spacecraft’s closest approach to Pluto on July 14, from the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Maryland, site of the mission operations center.

NASA also will provide comprehensive coverage on NASA Television, and the agency’s website and social media accounts as the spacecraft closes in on Pluto in the coming weeks.
The schedule for event coverage is subject to change, with daily updates posted online and in the New Horizons Media Center at APL. Highlights of the current schedule, all times EDT, include:
June 16, 23 and 30
11:30 a.m. -- Mission Updates
Weekly pre-flyby updates on NASA TV will provide an overview of the New Horizons mission, the spacecraft and its suite of instruments, the July 14 flyby, and a summary of Pluto science to date.
July 7- 12 
11:30 a.m. -- Final approach to Pluto; live daily mission updates on NASA TV
July 12
1 - 5 p.m. -- New Horizons Media Center opens at APL
July 13
11 a.m. – noon -- Media briefing: Mission Status and What to Expect. (live on NASA TV)
2:30 – 5:30 p.m. -- Panels: APL’s Endeavors in Space and the latest on New Horizons (no NASA TV coverage)
July 14
7:30 a.m. – Media Briefing: Arrival at Pluto, Inside the Pluto System and New Horizons’ Perilous Path (live on NASA TV)
At 7:49 a.m., the New Horizons spacecraft will make history as flies past Pluto, after a journey of more than nine years and 3 billion miles. For much of the day the New Horizons spacecraft will be out of communication with mission control as it gathers data on Pluto and its moons.
The moment of closest approach will be marked with a live NASA TV broadcast that includes a countdown, a discussion of images and data received thus far, and what’s expected next as New Horizons makes its way past Pluto and potentially dangerous debris. Follow the path of the spacecraft in real time with a visualization of the actual trajectory data, using NASA’s Eyes on Pluto.  
9 a.m. – noon -- Interview Opportunities (no NASA TV coverage)
Informal group briefings and availability for one-on-one interviews. An updated schedule will be posted in the New Horizons Media Center.
Noon – 3 p.m. – Panel Discussions (no NASA TV coverage)
New Horizons mission overview and history
Pluto system discoveries on approach
Mariner 4 and Pluto: 50 years to the day
8 – 9:15 p.m. -- NASA TV program, Phone Home, broadcast from APL Mission Control
NASA TV will share the suspenseful moments of this historic event with the public and museums around the world. The New Horizons spacecraft will send a preprogrammed signal after the close approach. The mission team on Earth should receive the signal at about 9:02 p.m. When New Horizons “phones home,” there will be a celebration of its success and the anticipation of data to come over the days and months ahead.  
9:15 – 10 p.m. -- Media Briefing: New Horizons Health and Mission Status (live on NASA TV)
July 15 
Noon – 3 p.m. -- Interview Opportunities (no NASA TV coverage)
Informal group briefings and availability for one-on-one interviews. An updated schedule will be posted in the New Horizons Media Center.
TBD -- Media Briefing: Seeing Pluto in a New Light (live on NASA TV)
Release of close-up images of Pluto’s surface and moons, along with initial science team reactions
New Horizons is the first mission to the Kuiper Belt, a gigantic zone of icy bodies and mysterious small objects orbiting beyond Neptune. This region also is known as the “third” zone of our solar system, beyond the inner rocky planets and outer gas giants.
APL designed, built and operates the New Horizons spacecraft, and manages the mission for NASA’s Science Mission Directorate in Washington. The Southwest Research Institute in San Antonio leads the science team, payload operations and encounter science planning. New Horizons is part of the New Frontiers Program, managed by NASA’s Marshall Space Flight Center in Huntsville, Alabama.
 
Quelle: NASA
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Update: 13.06.2015
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Complex Terrain Of Pluto Gets Clearer In New Horizons' Pics
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The surface of Pluto is coming into focus as NASA’s New Horizons spacecraft gets closer to its flyby next month.
A series of new pics snapped by the probe’s onboard Long Range Reconnaissance Imager (LORRI) at the end of May and start of June show that Pluto’s has a complex terrain, with very bright and very dark areas as well as grades in between.
“Even though the latest images were made from more than 30 million miles away, they show an increasingly complex surface with clear evidence of discrete equatorial bright and dark regions—some that may also have variations in brightness,” says New Horizons Principal Investigator Alan Stern, of the Southwest Research Institute, in a statement.
“We can also see that every face of Pluto is different and that Pluto’s northern hemisphere displays substantial dark terrains, though both Pluto’s darkest and its brightest known terrain units are just south of, or on, its equator. Why this is so is an emerging puzzle.”
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These images, taken by New Horizons’ Long Range Reconnaissance Imager (LORRI), show four different “faces” of Pluto as it rotates about its axis with a period of 6.4 days. (Credits: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute)
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New Horizons sends back raw, unprocessed images to the team’s scientists, who use a technique called deconvolution to sharpen up the pictures. In these latest images, the team has also upped the contrast to try to bring out as much detail as possible about the dwarf planet.
However, deconvolution can sometimes produce artifacts, so the scientists will have to compare images taken from closer range to be sure that these latest snaps are showing the full picture. Pluto also appears to not be a sphere in the images, but this is just a result of the processing of the pictures.
“We’re squeezing as much information as we can out of these images, and seeing details we’ve never seen before,” said New Horizons Project Scientists Hal Weaver, from the Johns Hopkins University Applied Physics Laboratory.
“We’ve seen evidence of light and dark spots in Hubble Space Telescope images and in previous New Horizons pictures, but these new images indicate an increasingly complex and nuanced surface. Now, we want to start to learn more about what these various surface units might be and what’s causing them. By early July we will have spectroscopic data to help pinpoint that.”
One theory that the scientists have already put forward is that a very bright area at one pole could be a polar ice-cap, but New Horizons needs to get closer to verify it.
The spacecraft will be the first to get close to the dwarf planet at the edge of our Solar System and is scheduled to make its closest flyby of Pluto on July 14.
New Horizons only gets one shot at the flyby, after which it will continue rocketing out towards the rest of the Kuiper Belt surrounding our neighbourhood planets.
Pluto and its five moons have been examined by telescope, but New Horizons’ close pass will give scientists a wealth of new information, so much that the craft will likely still be returning packets of data back to Earth up to 16 months after the rendezvous.
Quelle: Forbes
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Update: 16.06.2015
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Steady As She Goes: New Horizons Successfully Completes Small Course Correction Prior to Pluto Encounter


New Horizons will pass within 10,000 km of Pluto at its closest approach, which will put the spacecraft well within the orbits of Pluto’s outer moons, in a trajectory that will provide an additional protection against any potential hazards from dust debris rings or moonlets that may lurk around Pluto. Image Credit: NASA/JHU/APL
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With the clock swiftly ticking down to humanity’s eagerly anticipated first close-up reconnaissance of Pluto and its moons on 14 July, courtesy of NASA’s New Horizons spacecraft, mission controllers on the ground are continuously monitoring the robotic explorer’s fast-track course through interplanetary space and adjusting it when necessary, in order to ensure a successful fly by. To that end, New Horizons successfully executed a critical, small 45-second thruster burn on June 14, thus helping to keep the spacecraft where it should be along its path as it speeds through the Pluto system at a breakneck speed of 13.78 km per second just, four weeks from now.
Currently located more than 4.5 billion km away deep within the outer reaches of the Solar System, New Horizons’ one-of-a-kind close passage through the Pluto system is make-or-break. For this reason, a large part of the spacecraft’s activities ever since it was awakened from its electronic hibernation for the final time last December, comprised of a series of optical navigation campaigns that were pre-scheduled by the mission’s ground team to take place at various times throughout the entire approach phase to the Pluto system. In addition to the constant monitoring of its radio communication with Earth as New Horizons traversed the expanses of interplanetary space on its way to Pluto, these optical navigation campaigns were key for ground controllers to determine the exact position of the distant planet against the fixed background stars. This in turn allowed them to maintain New Horizons proper course towards Pluto and schedule for any appropriate correction maneuvers when necessary, without which the spacecraft would face the risk of veering off course and lose Pluto by hundreds or even thousands of kilometers.
This extensive preparation by the mission’s ground teams was put to good use on 14 June when New Horizons successfully executed a 45-second burn, which allowed it to change its velocity ever so slighty by just 52 centimeters per second. Even though that sounds like a miniscule change, it is nevertheless a significant one in orbital mechanics, without which New Horizons would miss its pre-scheduled arrival point at Pluto by 755 kilometers, while also arriving there a whole 84 seconds earlier than expected. With the help of NASA’s Deep Space Network antennas which are used to communicate with the spacecraft, ground controllers were able to receive telemetry confirming that the burn had gone according to plan on 6:23 a.m. EDT, more than 5 hours after it had been executed on 12:05 a.m.
This course correction is only the second one to be undertaken during New Horizons approach phase to Pluto, after a previous 93-second one which had taken place on March 10 and had reduced the spacecraft’s speed by 1.14 meters/second, while shifting it sideways by 3,442 kilometers toward the distant dwarf planet as seen from Earth. A third opportunity for a trajectory correction maneuver is also marked just a week from now, on June 24, to be followed by a fourth one on June 30 and a final one on July 4, just 10 days before New Horizons’ closest approach to Pluto. Whether these future trajectory correction maneuvers will take place however will depend on the results of the mission’s ground teams’ continuing study of the optical navigation images that are being returned by New Horizons’ onboard Long-Range Reconnaissance Imager, or LORRI, and the assessment in particular of the debris hazard to the spacecraft from any free-floating dust particles that may be present around Pluto. “We have a whole series of observations of which we are currently in the middle of as we approach [to Pluto], searching the system for moonlets or debris rings,” told me Dr.John Spencer, a science team member for New Horizons from the Southwest Research Institute in Boulder, Col, during a recent NASA media teleconference. “[Starting on early June], we will have the chance to divert the spacecraft if we see anything scary and then we will have a series of chances going [as well]. The last time we could divert the spacecraft to a different trajectory based on what we might see on the approach images, would be [approximately]14 days before closest approach, more or less on July the 1st”. So, we’re taking images up until that time, so that we’ll have the best possible information on which to make that decision”.
The chances for such a debris hazard are fortunately getting ever smaller as time goes by, as evidenced by the analysis of hundreds of 10-second exposures that were taken by LORRI between May 29-30 and June 5, which failed to reveal the pressence of any threatening dust debris rings or moonlets that could be four times dimmer than Pluto’s faintest known moon, Styx. Eve though the analysis of New Horizons’ optical navigations images will continue, the mission’s science team is fairly confident that the spacecraft will not face any such hazards in its course all the way through the Pluto system and beyond. “There’s a lot of chaos in the [Pluto] system, but there are parts of the system where things are pretty well-behaved and predictable”, says Spencer. “The big moon Charon in particular, is sweeping around Pluto in a very predictable and regular orbit every six days and it is very effective in clearing stuff out of anywhere near its own orbit in a matter of days. If you had a big cloud of debris somehow introduced into that region, it would be cleared out in days or weeks, and that is the part of the system that we’re flying through. We’re flying interior to the orbits of [Pluto’s] outer moons but right in the orbit of Charon. And Charon will do a lot of the [cleaning] work for us, despite whatever craziness is happening in the outer part of the system.”
With four weeks remaining prior to New Horizons’ historic fly by of Pluto, the mission’s next major milestone is set to occur on June 23, a date which will mark the start of Approach Phase 3, by which time New Horizons will be approximately 20 million kilometers away from Pluto. By then, the spacecraft’s onboard cameras will be returning images of Pluto and Charon of such clarity, that will allow scientists to study the atmospheric structures of this fascinating double dwarf planet system , which will allow for the creation of detailed global maps for both of these mysterious celestial objects.
Meanwhile, the resolution of New Horizons’ images continue to increase steadily with each passing day, until the time of closest approach on July 14, when the spacecraft will be able to take images of Pluto’s surface with a resolution of 0.1 km per pixel, which will finally reveal the mystifying distant planet’s topography in great detail for the first time in history. “Every day we break a new distance record to Pluto, and every day our data get better,” says Dr. Alan Stern, Principal Investigator for the New Horizons mission at the Southwest Research Institute, Boulder, Colorado. “Nothing like this kind of frontier, outer solar system exploration has happened since Voyager 2 was at Neptune way back in 1989. It’s exciting – come and watch as New Horizons turns points of light into a newly explored planetary system and its moons!”
Easily ranked as one of the biggest and most popular space exploration events of the whole decade, New Horizons’ upcoming close fly by of the Pluto system is bound to attract the attention of billions of people around the world.
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Ground controllers at the New Horizons Mission Operations Center at the Johns Hopkins University Applied Physics Laboratory in Laurel, MD, monitor the telemetry from New Horizons, following its successful course correction maneuver in June 14. Image Credit: Johns Hopkins University Applied Physics Laboratory
Quelle: AS
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Update: 17.06.2015
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Pluto just 4 weeks, 20 million miles away for spacecraft

NASA's New Horizons spacecraft is at Pluto's doorstep, following an incredible journey of nine years and 3 billion miles.
Four weeks from Tuesday — on July 14 — New Horizons will make its closest approach to Pluto. The spacecraft will fly within 7,750 miles, inside the orbits of Pluto's five known moons. That's the approximate distance between Seattle and Sydney.
It will be the first spacecraft to explore the tiny, icy world once considered a full-fledged planet.
As of Tuesday, New Horizons was just over 20 million miles from Pluto. That's closer than Earth is to neighbor Venus, at their closest point. Flight controllers fired a thruster on the spacecraft over the weekend to fine-tune its path.
"This is one charged-up team," principal investigator Alan Stern of the Southwest Research Institute in Boulder, Colorado said last week. "They know that they're getting to do something very special because nothing like this has happened" since Voyager 2's flyby of Neptune in 1989. NASA's first interplanetary success was at Venus, with Mariner 2 in 1962.
Stern added: "We're going to turn a point of light into a planet and its moons overnight in the next month."
The Johns Hopkins University's Applied Physics Laboratory in Laurel, Maryland, is operating the spacecraft for NASA. The lab also designed and built the relatively lightweight craft, about the size of a baby grand piano. It carries seven science instruments; the cameras have been photographing the planet since January.
The latest pictures, taken at the end of May and beginning of June, show large dark regions toward the bottom of Pluto. Scientists are eager to learn the size and shape of these dark spots, as well as their exact location. Images will keep improving with every step closer to Pluto.
"It's very fascinating to see this level of detail," deputy project scientist Cathy Olkin said during an update broadcast Tuesday.
Pluto was discovered by the late American astronomer Clyde Tombaugh in 1930. Its moons, the fifth unmasked as recently as 2012, also bear names related to the mythological underworld: big moon Charon and mini-moons Nix, Hydra, Kerberos and Styx.
More moons could be out there.
"We're going to write the textbook. We know very little about the Pluto system now," Stern said. "It's really a mission of raw exploration, flying into the unknown to see what's there."
New Horizons' $700 million mission began with a 2006 launch from Cape Canaveral, Florida.
Quelle: SCS
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Update: 20.06.2015
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Pluto and its Moon Charon, Now in Color


The first color movies from NASA’s New Horizons mission show Pluto and its largest moon, Charon, and the complex orbital dance of the two bodies, known as a double planet.
“It’s exciting to see Pluto and Charon in motion and in color,” says New Horizons Principal Investigator Alan Stern of the Southwest Research Institute (SwRI), Boulder, Colorado. “Even at this low resolution, we can see that Pluto and Charon have different colors—Pluto is beige-orange, while Charon is grey. Exactly why they are so different is the subject of debate.”
New Horizons will make its closest approach to Pluto on July 14, zipping by about 7,800 miles (12,500 kilometers) above the surface. It’s the first mission to Pluto and the Kuiper Belt, a relic of solar system formation beyond Neptune. Sending a spacecraft on this almost 3-billion mile journey will help us answer basic questions about the surface properties, atmospheres, and moons of the Pluto system.
These near-true color movies were assembled from images made in three colors — blue, red and near-infrared – by the Multicolor Visible Imaging Camera on the instrument known as Ralph, a “Honeymooners” reference that classic TV fans can appreciate. The images were taken on nine different occasions from May 29-June 3.
Although the two movies were prepared from the same images, they display the Pluto-Charon pair from different perspectives. One movie is “Pluto-centric”, meaning that Charon is shown as it moves in relation to Pluto, which is digitally centered in the movie. (The North Pole of Pluto is at the top.) Pluto makes one turn around its axis every 6 days, 9 hours and 17.6 minutes—the same amount of time that Charon rotates in its orbit. Looking closely at the images in this movie, one can detect a regular shift in Pluto’s brightness—due to the brighter and darker terrains on its differing faces.
The second movie is barycentric, meaning that both Pluto and Charon are shown in motion around the binary’s barycenter – the shared center of gravity between the two bodies as they do a planetary jig. Because Pluto is much more massive than Charon, the barycenter (marked by a small “x” in the movie) is much closer to Pluto than to Charon. 
As New Horizons closes in its intended target, the best is yet to come. “Color observations are going to get much, much better, eventually resolving the surfaces of Charon and Pluto at scales of just kilometers,” said Cathy Olkin, New Horizons deputy project scientist from SwRI. “This will help us unravel the nature of their surfaces and the way volatiles transport around their surfaces. I can’t wait; it’s just a few weeks away!”
The Johns Hopkins University Applied Physics Laboratory (APL) manages the New Horizons mission for NASA’s Science Mission Directorate in Washington. Alan Stern of the Southwest Research Institute (SwRI), headquartered in San Antonio, is the principal investigator and leads the mission. SwRI leads the science team, payload operations, and encounter science planning. New Horizons is part of the New Frontiers program, managed by NASA’s Marshall Space Flight Center in Huntsville, Alabama. APL designed, built and operates the spacecraft.
Ralph is a joint project between SwRI, Ball Aerospace in Boulder, Colorado, and NASA’s Goddard Space Flight Center, Greenbelt, Maryland.
Quelle: NASA
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Update: 23.06.2015
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NASA's New Horizons Probe Gives Us Our First Look at the 'Person in Pluto'

A combination of imagery from the LORRI and MVIC imagers on NASA's New Horizons probe provides a colorized view of Pluto (top) and its largest moon, Charon (bottom). NASA / JHUAPL / SwRI / Ian Regan
Humanity has looked up to the "Man in the Moon" for millennia, but this could be one of our first views of the "Person in Pluto."
The views are getting better and better as NASA's New Horizons spacecraft approaches Pluto for its July 14 flyby — and the pictures have begun revealing surface details. Ian Regan, an image-processing enthusiast from Plymouth, England, combined four images from New Horizons' Long Range Reconnaissance Imager with color data from the probe's Multispectral Visible Imaging Camera to produce an eerie colorized view of Pluto and its biggest moon, Charon.
The picture's orientation makes Pluto look as if it's a big-headed alien skull from a "Star Trek" episode, with two cratered eyes looking out toward the camera. It's a subtle effect, reminiscent of the Viking 1 orbiter's eerie "Face on Mars" image from 1976. Like that image of Mars' Cydonia region, a closer view can easily spoil the effect — so enjoy the Person in Pluto while you can.
Quelle: NBC-News
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New from NASA's New Horizons: Increasing Variety on Pluto's Close Approach Hemisphere, and a 'Dark Pole' on Charon
NASA’s New Horizons spacecraft doesn’t pass Pluto until July 14 – but the mission team is making new discoveries as the piano-sized probe bears down on the Pluto system.
In a long series of images obtained by New Horizons’ telescopic Long Range Reconnaissance Imager (LORRI) May 29-June 19, Pluto and its largest moon, Charon, appear to more than double in size. From this rapidly improving imagery, scientists on the New Horizons team have found that the “close approach hemisphere” on Pluto that New Horizons will fly over has the greatest variety of terrain types seen on the planet so far. They have also discovered that Charon has a “dark pole” – a mysterious dark region that forms a kind of anti-polar cap.
"This system is just amazing," said Alan Stern, New Horizons Principal Investigator, from the Southwest Research Institute, Boulder, Colorado. "The science team is just ecstatic with what we see on Pluto’s close approach hemisphere: Every terrain type we see on the planet—including both the brightest and darkest surface areas —are represented there, it’s a wonderland!
"And about Charon—wow—I don’t think anyone expected Charon to reveal a mystery like dark terrains at its pole," he continued. "Who ordered that?"
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These images, taken by New Horizons' Long Range Reconnaissance Imager (LORRI), show numerous large-scale features on Pluto's surface. When various large, dark and bright regions appear near limbs, they give Pluto a distinct, but false, non-spherical appearance. Pluto is known to be almost perfectly spherical from previous data. These images are displayed at four times the native LORRI image size, and have been processed using a method called deconvolution, which sharpens the original images to enhance features on Pluto.
Credits: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute
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New Horizons scientists use a technique called deconvolution to sharpen the raw, unprocessed pictures that the spacecraft beams back to Earth; the contrast in these latest images has also been stretched to bring out additional details. Deconvolution can occasionally produce artifacts, so the team will be carefully reviewing newer images taken from closer range to determine whether some of the tantalizing details seen in these images persist. Pluto’s non-spherical appearance in these images is not real; it results from a combination of the image-processing technique and Pluto’s large variations in surface brightness.
"The unambiguous detection of bright and dark terrain units on both Pluto and Charon indicates a wide range of diverse landscapes across the pair," said science team co-investigator and imaging lead Jeff Moore, of NASA Ames Research Center, Mountain View, California. “For example, the bright fringe we see on Pluto may represent frost deposited from an evaporating polar cap, which is now in summer sun.”
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These recent images show the discovery of significant surface details on Pluto’s largest moon, Charon. They were taken by the New Horizons Long Range Reconnaissance Imager (LORRI) on June 18, 2015. The image on the left is the original image, displayed at four times the native LORRI image size. After applying a technique that sharpens an image called deconvolution, details become visible on Charon, including a distinct dark pole. Deconvolution can occasionally introduce "false" details, so the finest details in these pictures will need to be confirmed by images taken from closer range in the next few weeks.
Credits: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute
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New Horizons is approximately 2.9 billion miles (4.7 billion kilometers) from Earth and just 16 million miles (25 million kilometers) from Pluto. The spacecraft and payload are in good health and operating normally.
Quelle: NASA  
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Update: 25.06.2015
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SOFIA to work with New Horizons during upcoming Pluto encounter

 

NASA’s high-flying infrared observatory is Down Under this week to observe the southern sky, and to make a unique observation ahead of New Horizons' historic encounter with Pluto and its moons next month. The aircraft is an unusual airborne observatory known as SOFIA, or the Stratospheric Observatory For Infrared Astronomy. SOFIA began observations in 2010, and consists of a 2.5-meter telescope mounted aboard a modified Boeing 747SP wide-body aircraft. In addition to numerous southern sky targets, astronomers hope to catch a rare occultation of a +12th magnitude star by the planet Pluto on June 29. Observers will utilize the High Speed Imaging Photometer for Occultations (HIPO) and the Focal Plane Imager (FPI) to record the brief, seconds-long event. “SOFIA’s 2013 deployment to New Zealand and the resulting observations were of great scientific value,” SOFIA program manager Eddie Zavala said in a recent press release. “Our research staff and guest investigators have been looking forward to building on that success with our return to the Southern Hemisphere this month.” This occultation gives astronomers a chance to measure the atmosphere of Pluto and its composition just before New Horizons' July 14 encounter. New Horizons will also pass through the shadows of Pluto and Charon and witness two radio occultations—think of it as the most distant solar eclipses ever recorded—for comparison. And you never know what other types of serendipitous discoveries might result. A similar occultation of a background star by Uranus was witnessed by SOFIA’s predecessor the Kuiper Airborne Observatory in 1977. This event revealed the ring system of Uranus, as the star's light dimmed two times more than expected as the planet passed in front of it.

Quelle: SEN

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Update: 27.06.2015

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What Is Glittering at Pluto’s North Pole?

Pluto and Charon are getting clearer every day.
Photo by NASA/JHUAPL/SwRI
As the New Horizons spacecraft nears Pluto, more details are coming into view, and we are beginning to see surface features on the tiny world.
And that means we’ll see things that are … odd. Perhaps “as yet unexplained” is a better term, since we’re seeing these markings for the first time in human history. The press releases have been amazing, but the images released have been enlarged and processed in complex ways to bring out details.
But as the probe gets closer, we can see details without such means. The raw data are posted online within hours of them being transmitted back to Earth, and that means they are available for perusal.
I was looking at a pair of fresh ones taken just today, June 25, at 05:37 UTC (just after midnight, more or less, U.S. time), when New Horizons was just 22.9 million kilometers from Pluto. They’re amazing. Both Pluto and its large moon Charon show all kinds of features, as you can see at the top of this article (the only processing I did was a straight enlargement and a brightness/contrast fiddle). Overall, Charon is much darker than Pluto, but even then surface features are clearly visible.
But that bright spot on Pluto surprised me. That’s near its north pole, and it’s been seen before in earlier images, basically as a splotch. In this image it’s quite obvious.
I wondered if perhaps this was an image artifact, like a particle hit on the detector, but in fact it’s the same in the other image taken 30 seconds earlier. Here are the two shots side by side:
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Pictures of Pluto taken at 05:37:30 (left) and 30 seconds earlier (right), enlarged and contrast enhanced.
Photo by NASA/JHUAPL/SwRI
The spot is very small, probably on the same scale as a single pixel or two in New Horizon’s long-range camera. That means a slight change in the pointing can make its shape look different. Remember too this image is enlarged by a factor of about 10, which can play with the shape as well. While the shape you see may not be real, the brightness contrast is.
But the important thing to note is that it’s seen in both pictures. I’ll note too that Pluto was in a different spot in the camera’s field of view, too, so this isn’t some bad lone pixel either, messing with the shot. This bright spot is quite real. Measuring the pixel brightnesses, it looks to be about twice as bright as the surface around it.
Right now, Pluto is only a couple of dozen pixels across in the long-range camera’s view. New Horizons is moving so rapidly that in 10 days Pluto will be twice this size, and will double again five days after that. Features that are tantalizingly fuzzy now will continue to sharpen, and then we’ll see Pluto as it truly is.
Is this spot at the north pole a fresh impact? Is it nitrogen in its atmosphere freezing out as Pluto slowly moves away from the Sun on its elliptical orbit? Is it one big spot or a lot of little ones (like the weird ones we see on Ceres)?
Give it a couple of weeks. Because that's how close we are. After more than nine years and 5 billion kilometers of travel, New Horizons is about to give us quite a show.
Quelle: Bad Astronomy

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Update: 1.07.2015

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New Horizons ‘Speeds Up’ on Final Approach to Pluto

In the New Horizons Mission Operations Center at the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, flight controllers (from left) Chris Regan and Becca Sepan monitor data from NASA’s New Horizons spacecraft on June 30, after a short course-correction maneuver refined New Horizons path toward a flyby of Pluto on July 14.

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With just two weeks to go before its historic July 14 flight past Pluto, NASA’s New Horizons spacecraft tapped the accelerator late last night and tweaked its path toward the Pluto system.
The 23-second thruster burst was the third and final planned targeting maneuver of New Horizons’ approach phase to Pluto; it was also the smallest of the nine course corrections since New Horizons launched in January 2006. It bumped the spacecraft’s velocity by just 27 centimeters per second – about one-half mile per hour – slightly adjusting its arrival time and position at a flyby close-approach target point approximately 7,750 miles (12,500 kilometers) above Pluto’s surface.
While it may appear to be a minute adjustment for a spacecraft moving 32,500 miles per hour, the impact is significant. New Horizons Mission Design Lead Yanping Guo, of the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, says without the adjustment, New Horizons would have arrived 20 seconds late and 114 miles (184 kilometers) off-target from the spot where it will measure the properties of Pluto’s atmosphere. Those measurements depend on radio signals being sent from Earth to New Horizons at precise times as the spacecraft flies through the shadows of Pluto and Pluto’s largest moon, Charon.
In fact, timing and accuracy are critical for all New Horizons flyby observations, since those commands are stored in the spacecraft’s computers and programmed to “execute” at exact times.
This latest shift was based on radio-tracking data on the spacecraft and range-to-Pluto measurements made by optical-navigation imaging of the Pluto system taken by New Horizons in recent weeks. Using commands transmitted to the spacecraft on June 28, the thrusters began firing at 11:01 p.m. EDT on June 29 and stopped 23 seconds later. Telemetry indicating the spacecraft was healthy and that the maneuver went as designed began reaching the New Horizons Mission Operations Center at APL, through NASA’s Deep Space Network at 5:30 a.m. EDT on June 30.
“We are really on the final path,” said New Horizons Project Manager Glen Fountain, of APL. “It just gets better and more exciting every day.”
“This maneuver was perfectly performed by the spacecraft and its operations team,” added mission principal investigator Alan Stern, of Southwest Research Institute, Boulder, Colorado. “Now we’re set to fly right down the middle of the optimal approach corridor.”
New Horizons is now about 10 million miles (16 million kilometers) from the Pluto system – some 2.95 billion miles (4.75 billion kilometers) from Earth.
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In the New Horizons Mission Operations Center at the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, Mission Operations Manager Alice Bowman and operations team member Karl Whittenburg watch for data confirming that the Pluto-bound NASA spacecraft successfully executed a course correction maneuver on June 30.
Quelle: NASA

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New Horizons Update: Methane Detected; New Images of Pluto and Charon; Sunrise/Sunset Observations

The location of the New Horizons Ralph instrument, which detected methane on Pluto, is shown. The inset is a false color image of Pluto and Charon in infrared light; pink indicates methane on Pluto’s surface.
Credits: Photo credit: NASA/Johns Hopkins Applied Physics Laboratory/Southwest Research Institute
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Yes, there is methane on Pluto, and, no, it doesn’t come from cows. The infrared spectrometer on NASA’s Pluto-bound New Horizons spacecraft has detected frozen methane on Pluto’s surface; Earth-based astronomers first observed the chemical compound on Pluto in 1976.
“We already knew there was methane on Pluto, but these are our first detections,” said Will Grundy, the New Horizons Surface Composition team leader with the Lowell Observatory in Flagstaff, Arizona. “Soon we will know if there are differences in the presence of methane ice from one part of Pluto to another.”
Methane (chemical formula CH4) is an odorless, colorless gas that is present underground and in the atmosphere on Earth. On Pluto, methane may be primordial, inherited from the solar nebula from which the solar system formed 4.5 billion years ago. Methane was originally detected on Pluto’s surface by a team of ground-based astronomers led by New Horizons team member Dale Cruikshank, of NASA’s Ames Research Center, Mountain View, California.
Come Fly with New Horizons on its Approach to Pluto
Images from New Horizons show the view from aboard the spacecraft closes in on the Pluto system for a July 14 flyby.
This time-lapse approach movie was made from images from the Long Range Reconnaissance Imager (LORRI) camera aboard New Horizons spacecraft taken between May 28 and June 25, 2015. During that time the spacecraft distance to Pluto decreased almost threefold, from about 35 million miles to 14 million miles (56 million kilometers to 22 million kilometers). The images show Pluto and its largest moon, Charon, growing in apparent size as New Horizons closes in. As it rotates, Pluto displays a strongly contrasting surface dominated by a bright northern hemisphere, with a discontinuous band of darker material running along the equator. Charon has a dark polar region, and there are indications of brightness variations at lower latitudes.
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“Alice” Instrument Practices for Sunset and Sunrise Observations of Pluto’s Atmosphere
The New Horizons spacecraft has made a critical observation in preparation for its upcoming observations of Pluto’s tenuous atmosphere. Just hours after its flyby of Pluto on July 14, the spacecraft will observe sunlight passing through the planet’s atmosphere, to help scientists determine the atmosphere’s composition. “It will be as if Pluto were illuminated from behind by a trillion-watt light bulb,” said Randy Gladstone, a New Horizons scientist from Southwest Research Institute, San Antonio. On June 16, New Horizons’ Alice ultraviolet imaging spectrograph successfully performed a test observation of the sun from 3.1 billion miles away (5 billion kilometers), which will be used to interpret the July 14 observations.
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This spectrum of the Sun obtained by New Horizons’ Alice instrument on June 16, 2015, will be used to interpret the spacecraft’s upcoming observations of Pluto’s atmosphere.
Credits: Photo credit: NASA/Johns Hopkins Applied Physics Laboratory/Southwest Research Institute
New Horizons is now less than 11 million miles (18 million kilometers) from the Pluto system. The spacecraft is healthy and all systems are operating normally. 
The Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, designed, built, and operates the New Horizons spacecraft, and manages the mission for NASA’s Science Mission Directorate. The Southwest Research Institute, based in San Antonio, leads the science team, payload operations and encounter science planning. New Horizons is part of the New Frontiers Program managed by NASA’s Marshall Space Flight Center in Huntsville, Alabama.
Quelle: NASA
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Update: 2.07.2015
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Pluto's Black Spots and Charon's Dark Pole Grow in New Horizons View

New color images from NASA's New Horizons spacecraft show two very different faces of the mysterious dwarf planet, one with a series of intriguing spots along the equator that are evenly spaced. The images combine black-and-white data from the spacecraft's Long Range Reconnaissance Imager with lower-resolution color data from the Ralph instrument. NASA / JHUAPL / SwRI
NASA's New Horizons mission is kicking off its climactic month of July with amazing views that clearly show Pluto's black spots and Charon's dark pole growing in the spacecraft's virtual windshield.
After traveling for nine years and 3 billion miles, the New Horizons probe is less than two weeks and 9.5 million miles (15.2 million kilometers) away from Pluto. Every day is bringing improvements in image size and quality. Images from the Long Range Reconnaissance Imager, or LORRI, show patterns of dark and light areas on Pluto — including that dark patch, which looks a lot like a racing stripe, and a series of spots.
"We don't know what the spots are," the mission's principal investigator, Alan Stern of the Southwest Research Institute, said in news release, "and we can't wait to find out."
In a Reddit "Ask Me Anything" chat session, New Horizons team member Amanda Zangari compared Pluto to Triton, a moon of Neptune. Researchers believe Triton was a cousin of Pluto's in the icy Kuiper Belt that happened to be captured in Neptunian orbit:
"Both Pluto and Triton have a dark equatorial region and bright poles. Among the team, we've been impressed at how much they match. Pluto's dark patch is quite different though. Triton's got geysers, plumes and cantaloupe terrain and not a lot of craters. We won't know if Pluto is like that until we get closer, but it's within the realm of possibility."
Zangari wrote that the biggest surprise was the appearance of a dark circle at one of Charon's poles:
"We all think this is hysterical, because Charon had a dark pole in the simulation we did of what the encounter would be like. It was also a surprise because Charon's rotational light curve (i.e. its pattern of light and dark) is very subtle, so while we knew Pluto was going to have dark spots, Charon very well could have been uniform."
All these features will become clearer over the next two weeks, leading up New Horizons' Pluto flyby on July 14, when the piano-sized spacecraft will come within 7,800 miles (12,500 kilometers) of the dwarf planet's surface.
In addition to the visuals, the team is getting better readings about Pluto's composition. This week, scientists announced that they have begun to detect methane on the surface.
"We already knew there was methane on Pluto, but these are our first detections," Lowell Observatory planetary scientist Will Grundy, who heads New Horizons' surface composition team, said in a NASA news release. "Soon we will know if there are differences in the presence of methane ice from one part of Pluto to another."
There'll be a steady drumbeat of pictures, videos and live events — including Pluto TV webcasts and a series of "Plutopalooza" presentations across the country. To find a Plutopalooza near you, check out the schedules from New Horizons as well as NASA's Museum Alliance and Solar Systems Ambassadors Program.
Quelle: NBC-News
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NASA’s New Horizons Spacecraft Stays the Course to Pluto

These images show the difference between two sets of 48 combined 10-second exposures with New Horizons' Long Range Reconnaissance Imager (LORRI) camera, taken at 8:40 UTC and 10:25 UTC on June 26, 2015, from a range of 21.5 million kilometers (approximately 13 million miles) to Pluto. The known small moons, Nix, Hydra, Kerberos and Styx, are visible as adjacent bright and dark pairs of dots, due to their motion in the 105 minutes between the two image sets.
Credits: NASA/JHU-APL/SwRI
NASA’s New Horizons spacecraft is getting a final “all clear” as it speeds closer to its historic July 14 flyby of Pluto and the dwarf planet’s five moons.
After seven weeks of detailed searches for dust clouds, rings, and other potential hazards, the New Horizons team has decided the spacecraft will remain on its original path through the Pluto system instead of making a late course correction to detour around any hazards. Because New Horizons is traveling at 30,800 mph (49,600 kph), a particle as small as a grain of rice could be lethal.
“We’re breathing a collective sigh of relief knowing that the way appears to be clear,” said Jim Green, director of planetary science at NASA. “The science payoff will be richer as we gather data from the optimal flight path, as opposed to having to conduct observations from one of the back-up trajectories.”
Mission scientists have been using the spacecraft’s most powerful telescopic camera, the Long Range Reconnaissance Imager (LORRI), to look for potential hazards, such as small moons, rings, or dust, since mid-May. The decision on whether to keep the spacecraft on its original course or adopt a Safe Haven by Other Trajectory, or "SHBOT" path, had to be made this week since the last opportunity to maneuver New Horizons onto an alternate trajectory is July 4.
“Not finding new moons or rings present is a bit of a scientific surprise to most of us,” said principal investigator Alan Stern of the Southwest Research Institute (SwRI) in Boulder, Colorado. “But as a result, no engine burn is needed to steer clear of potential hazards. We presented these data to NASA for review and received approval to proceed on course and plan. We are ‘go’ for the best of our planned Pluto encounter trajectories.”
New Horizons formed a hazard analysis team in 2011, after the discovery of Pluto’s fourth moon, Kerberos, raised concerns the cratering of these moons by small debris from the outer area of the solar system known as the Kuiper Belt, could spread additional hazardous debris into New Horizons’ path. Mission engineers re-tested spare spacecraft blanketing and parts back on Earth to determine how well they would stand up to particle impacts, and scientists modeled the likely formation and locations of rings and debris in the Pluto system. By the time New Horizons’ cameras were close enough to Pluto to start the search last month, the team had already estimated the chances of a catastrophic incident at far less than one percent.
The images used in the latest searches that clear
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