After traveling nearly 3 billion miles over the past nine and a half years, NASA’s New Horizons spacecraft is within hours of its rendezvous with Pluto. Back in 2006, when the space probe was launched, Pluto was classified as the ninth planet in the solar system, and was known to have three moons. During the long journey to this distant icy world, Pluto was reclassified as a dwarf planet, one of many smaller bodies orbiting the sun, and another two moons were discovered. In 2007, New Horizons flew past Jupiter and its moons on the way to Pluto, capturing many spectacular images. On the morning of July 14, 2015 (Earth time, Western Hemisphere), New Horizons will speed past the Pluto system at about 9 miles (14 kilometers) per second, making as many observations as possible. In the hours and days following, it will be sending the data to Earth, on its way to theKuiper belt, with plans to target another smaller body sometime around 2018. (More Pluto images will be added here as they become available.)
- An Atlas V rocket carrying the New Horizons spacecraft on a mission to the planet Pluto lifts off from launch pad 41 at the Cape Canaveral Air Force Station in Florida on January 19, 2006.Terry Renna / AP
- Clyde Tombaugh, the amateur astronomer who discovered Pluto on February 18, 1930, pictured in 1931. Tombaugh was working as a researcher for the Lowell Observatory in Flagstaff, Arizona, searching for a predicted “Planet X,” when he made the discovery by comparing photographic plates made of star fields over the course of several nights.AP
- In 2003, this was the most detailed image of the surface of Pluto available, as constructed from multiple photographs taken by NASA’s Hubble Space Telescope from 2002 to 2003.NASA / Reuters
- An aluminum canister containing the ashes of Clyde Tombaugh, the American astronomer who discovered Pluto in 1930, attached to NASA's New Horizons spacecraft. Tombaugh passed away in 1997 at the age of 90. On Tuesday, July 14, 2015, the spacecraft is scheduled to pass within 7,800 miles of Pluto, which he discovered 85 years ago.Johns Hopkins University Applied Physics Laboratory / AP
- Members of the media garbed in protective uniforms view NASA's New Horizons spacecraft on November 4, 2005, in the Payload Hazardous Servicing Facility at Kennedy Space Center.Bruce Weaver / AFP / Getty
- A 2004 Florida quarter is prepared for installation on the New Horizons spacecraft in Kennedy Space Center's Payload Hazardous Servicing Facility on December 7, 2005. The new quarter, engraved with the "Gateway to Discovery" design, will accompany New Horizons on its 3-billion-mile journey to the dwarf planet Pluto and its moon, Charon. Although appropriate for the mission to carry the coin from the state that symbolizes space exploration, it will also serve a practical purpose: Scientists are using the quarter as a spin-balance weight.NASA
- Patricia Tombaugh, 92, of Las Cruces, New Mexico, stands next to a model of the New Horizons spacecraft at the Kennedy Space Center on January 15, 2006. Her late husband, Clyde Tombaugh discovered the dwarf planet Pluto in 1930.John Raoux / AP
- In the Payload Hazardous Servicing Facility at the John F. Kennedy Space Center in Florida, two fairing sections move into place around the New Horizons spacecraft for encapsulation on December 13, 2005. The fairing protects the spacecraft during launch and flight through the atmosphere. Once out of the atmosphere, the fairing is jettisoned.NASA
- A white arrow marks Pluto in this New Horizons Long Range Reconnaissance Imager (LORRI) picture taken on September 21, 2006. Seen at a distance of about 4.2 billion kilometers (2.6 billion miles) from the spacecraft, Pluto is little more than a faint point of light among a dense field of stars. Mission scientists knew they had Pluto in their sights when LORRI detected an unresolved “point” in Pluto's predicted position, moving at the planet's expected motion across the constellation of Sagittarius near the plane of the Milky Way galaxy.JHUAPL / SWRI / NASA
- Pluto's moons Hydra and Nix were first spotted by the Hubble Space Telescope in 2005. This follow-up image helped confirm the discovery. The confirmation reinforces the emerging view that the Kuiper Belt, a swarm of icy bodies encircling the solar system beyond Neptune, may be more complex and dynamic than astronomers once thought. The moons' orbits are in the same plane as the orbit of the much larger satellite Charon (discovered in 1978). This likely means the moons were not captured, but instead were born, along with Charon, in what is commonly theorized to have been a titanic collision between two Pluto-sized objects over 4 billion years ago. Astronomers believe that the formation of the Pluto system is similar to that of our Earth and Moon. In both cases a comparable-sized body slammed into the parent planet. Simulations show that debris from the collision would go into an orbit around the planet and coalesce to form one or more satellites.NASA
- The New Horizons Long Range Reconnaissance Imager took this 4-millisecond exposure of Jupiter and two of its moons on January 17, 2007. The spacecraft was 42.5 million miles (68.5 million kilometers) from Jupiter, closing in on the giant planet at 41,500 miles (66,790 kilometers) per hour. The volcanic moon Io is the closest moon to the right of Jupiter; the icy moon Ganymede is to Io's right. The shadows of each satellite are visible atop Jupiter's clouds; Ganymede's shadow is draped over Jupiter's northwestern limb.JHUAPL / SWRI / NASA
- This beautiful image of the crescents of volcanic Io and more sedate Europa is a combination of two New Horizons images taken on March 2, 2007, about two days after New Horizons made its closest approach to Jupiter. This image was taken from a range of 2.8 million miles (4.6 million kilometers) from Io and 2.4 million miles (3.8 million kilometers) from Europa. Although the moons appear close together in this view, a gulf of 490,000 miles (790,000 kilometers) separates them. Io’s night side is lit up by light reflected from Jupiter, which is off the frame to the right. Europa's night side is dark, in contrast to Io, because this side of Europa faces away from Jupiter. Here Io steals the show with its beautiful display of volcanic activity. Three volcanic plumes are visible. Most conspicuous is the enormous 190-mile- (300-kilometer-) high plume from the Tvashtar volcano at the 11 o'clock position on Io’s disk. Two much smaller plumes are also visible: that from the volcano Prometheus, at the 9 o'clock position, and from the volcano Amirani, seen between Prometheus and Tvashtar. The Tvashtar plume appears blue because of the scattering of light by tiny dust particles ejected by the volcanoes, similar to the blue appearance of smoke.JHUAPL / SWRI / NASA
- The New Horizons Multispectral Visible Imaging Camera (MVIC) snapped this incredibly detailed picture of Jupiter's high-altitude clouds on February 28, 2007, when the spacecraft was only 1.4 million miles (2.3 million kilometers) from the solar system's largest planet.JHUAPL / SWRI / NASA
- This five-frame sequence of New Horizons images captured the giant plume from Io's Tvashtar volcano on March 1, 2007, at a distance of 2.4 million miles (3.8 million kilometers).JHUAPL / SWRI / NASA
- New Horizons took this image of the icy moon Europa rising above Jupiter’s cloud tops after the spacecraft’s closest approach to Jupiter. The spacecraft was 1.4 million miles (2.3 million kilometers) from Jupiter and 1.8 million miles (3 million kilometers) from Europa when the picture was taken.JHUAPL / SWRI / NASA
- This image, taken by the Hubble Space Telescope, shows five moons orbiting the distant, icy dwarf planet Pluto. The circle marks the newly discovered moon, designated S/2012 (134340) 1, or P5, as photographed by Hubble’s Wide Field Camera 3 on July 7, 2012. The moon is estimated to be approximately 6 to 16 miles (10 to 25 kilometers) across, in a 59-000-mile (95,000-kilometer) diameter circular orbit around Pluto that is assumed to be aligned in the same plane as the other satellites in the system. The darker stripe in the center of the image is because the picture is constructed from a long exposure—designed to capture the comparatively faint satellites of Nix, Hydra, P4, and S/2012 (134340) 1—and a shorter exposure designed to capture Pluto and Charon, which are much brighter.M Showalter / NASA / ESA / AFP / Getty
- An April 9, 2015 picture of Pluto and its largest moon, Charon, taken by the Ralph color imager aboard NASA’s New Horizons spacecraft. It was the first color image ever made of the Pluto system by a spacecraft on approach, according to NASA. The image was made from a distance of about 71 million miles (115 million kilometers), roughly the distance from the Sun to Venus.JHUAPL / SWRI / NASA / Reuters
- The first color movie from NASA's New Horizons mission showed Pluto and its largest moon, Charon, in their complex orbital dance. This near-true color movie was assembled from images made in three colors—blue, red and near-infrared—by the Multicolor Visible Imaging Camera on the instrument known as Ralph. The images were taken on nine different occasions from May 29 to June 3, 2015. The 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.JHUAPL / SWRI / NASA
- This image, taken by New Horizons’ Long Range Reconnaissance Imager (LORRI), shows numerous large-scale features on Pluto's surface as the spacecraft approached in early 2015.JHUAPL / SWRI / NASA
- 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.JHUAPL / SWRI / NASA
- New Horizons was about 3.7 million miles (6 million kilometers) from Pluto and Charon when it snapped this portrait late on July 8, 2015. Color information from previous observations was added to this image.JHUAPL / SWRI / NASA
- This color version of a New Horizons Long Range Reconnaissance Imager (LORRI) picture of Pluto taken July 3, 2015, was created by adding color data from the Ralph instrument gathered earlier in the mission. The LORRI image was taken from a range of 7.8 million miles (12.5 million kilometers.)JHUAPL / SWRI / NASA
- A portrait from the final approach. Pluto and Charon display striking color and brightness contrast in this composite image from July 11, 2015, showing high-resolution black-and-white LORRI images colorized with Ralph data collected from the last rotation of Pluto.NASA-JHUAPL-SWRI
- Charon’s newly discovered system of chasms, larger than the Grand Canyon on Earth, rotates out of view in New Horizons’ sharpest image yet of the Texas-sized moon. It’s trailed by a large equatorial impact crater that is ringed by bright rays of ejected material. In this latest image, the dark north polar region is displaying new and intriguing patterns. This image was taken on July 12 from a distance of 1.6 million miles (2.5 million kilometers).JHUAPL / SWRI / NASA
- Pluto’s bright, mysterious “heart” is rotating into view, ready for its close-up on close approach, in this image taken by New Horizons on July 12 from a distance of 1.6 million miles (2.5 million kilometers). It is the target of the highest-resolution images that will be taken during the spacecraft’s closest approach to Pluto on July 14. The intriguing “bulls-eye” feature at right is rotating out of view, and will not be seen in greater detail.JHUAPL / SWRI / NASA
- Members of the New Horizons science team react to seeing the spacecraft's last and sharpest image of Pluto before closest approach later in the day at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Maryland, on July 14, 2015.Bill Ingalls / NASA / Reuters
Pluto photographs thrill Nasa scientists after nine-year mission
Cheers, whoops and flag waving broke out at Nasa’s New Horizons control centre as scientists celebrated the spacecraft’s dramatic flyby of Pluto, considered the last unexplored world in the solar system.
The probe shot past at more than 28,000mph (45,000 km/h) at 12.49pm BST (7.49am ET) on a trajectory that brought the fastest spacecraft ever to leave Earth’s orbit within 7,770 miles of Pluto’s surface.
The moment, played out on Tuesday to the sound of The Final Countdown by the 1980s glam metal band Europe, marked a historic achievement for the US, which can now claim to be the only nation to have visited every planet in the classical solar system.
“It feels good,” said Alan Stern, lead scientist on the mission. “So many people put so much work into this around the country. We’ve completed the initial reconnaissance of the solar system, an endeavour started under President Kennedy.”
John Grunsfeld, head of Nasa’s science mission directorate, said that images beamed back from New Horizons on its approach showed Pluto to be an “extraordinarily interesting and complex world”.
“It’s just amazing. It’s truly a hallmark in human history,” he said of the encounter with Pluto. “It’s been an incredible voyage.”
Stephen Hawking, the Cambridge cosmologist, joined in congratulating the New Horizons team in a recorded message. “Billions of miles from Earth this little robotic spacecraft will show us that first glimpse of mysterious Pluto, a distant icy world on the edge of our solar system. The revelations of New Horizons may help us to understand better how our solar system was formed. We explore because we are human and we long to know,” he said.
Bristling with cameras and other instruments, the New Horizons probe was programmed to gather a wealth of images and data as it sped past Pluto and its five small moons, Charon, Styx, Nix, Hydra and Kerberos.
Images beamed back from New Horizons have shown Pluto in shades of red and orange, with hints of valleys, mountains and craters. On Tuesday Nasa released a new image of Pluto. The picture was taken at about 9pm BST (4pm ET) on 13 July, about 16 hours before the moment of closest approach. The spacecraft was 476,000 miles from the surface.
Though Pluto has a varied terrain, with dark patches on the equator and brighter regions to the north, its surface looks younger and smoother than that of its largest moon, Charon. The reason may be geological activity, which refreshes the body’s surface.
Sensors on New Horizons detected Pluto’s thin nitrogen atmosphere extending far out into space. Scientists believe it may shed snow, with flakes tumbling down to the surface before vaporising back into the atmosphere.
Other measurements from the probe have found that Pluto is larger than previously thought, at 1,470 miles across. That means it contains more ice beneath its surface and less rock than scientists had anticipated.
Mission scientists at Johns Hopkins University in Baltimore were out of contact with the spacecraft as it hurtled past the icy body 3bn miles from Earth. Instead the probe captured images and took measurements automatically and stored them on board to send back later.
Alice Bowman, missions operations manager, said that when the spacecraft fell silent on Monday, as expected, scientists stayed in the operations centre. “We wanted to be with it,” she said. “We always talk about the spacecraft being a child, a baby, a teenager. We lost signal as planned last night, and there was nothing anybody on the operations team could do but trust we’d prepared it well.”
At such a great distance, direct control from the ground is impossible, because radio signals take more than nine hours to travel to the spacecraft and back again. It will take 16 months to beam all of New Horizon’s data back to Earth.
Scientists now face an agonising wait for news from the spacecraft, which is due to call home at 2am BST Wednesday (9pm ET Tuesday). Only when that 15 minute-long signal is received will Nasa officials know whether New Horizons survived the flyby.
One of the greatest hazards the spacecraft faces is dust that may form a hazy cloud around Pluto after being knocked off its moons by meteorite strikes. Hal Weaver, a scientist on the mission, said that colliding with a dust particle the size of a grain of rice could potentially destroy the mission. But the risk of such a catastrophic failure was low, at less than one in 10,000.
“I am feeling a little bit nervous, but I have absolute confidence it’s going to do what it needs to do, and turn around and send us that burst of data,” Bowman said.
Stern was equally confident that New Horizons would survive the flyby: “I don’t think we’re going to lose the spacecraft.”
The loss would be tremendous, should it happen. About 99% of the data is still on the spacecraft. “Some of the most important stuff is in that. It would be a great disappointment if New Horizons is lost,” Stern said.
New Horizons blasted off in January 2006, carrying the ashes of Clyde Tombaugh, the astronomer who discovered Pluto in 1930. Several months later, astronomers at the International Astronomical Union voted to change the definition of the word “planet”, a move that downgraded Pluto to the more diminutive “dwarf planet”. The flyby may resurrect the debate and see Pluto restored to full planetary status.
In a live interview on Nasa TV on Tuesday, Charles Bolden, Nasa’s chief administrator, said he hoped the scientists would reconsider the name. “I call it a planet, but I’m not the rule maker,” he said, adding that arguments over Pluto’s status should not detract from the achievement. “It should be a day of incredible pride.”
Pluto lies in a region of space at the edge of the solar system called the Kuiper belt. Astronomers call it the third zone of space. The first zone contains the rocky, terrestrial planets of Mercury, Venus, Earth and Mars. The second zone is home to the gas giants, Jupiter, Saturn, Uranus and Neptune. Alongside the Pluto system in the Kuiper belt are comets and more than 100,000 miniature worlds.
New Horizons is expected to continue its mission into the Kuiper belt. The spacecraft is powered by a nuclear generator that runs on plutonium, a substance named after the dwarf planet. The generator should run until the 2030s, when New Horizons will be 100 times further away than Earth is from the sun.
http://www.space.com/20525-jupiter-moon-s-volcanic-plume-seen-by-spacecraft-video.html
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