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Pluto flyby: Nasa probe New Horizons arrives nine years after leaving Earth New Horizons: Nasa probe flies past Pluto nine years after leaving Earth
(35 minutes later)
Cheers, whoops and flag-waving broke out in Nasa’s New Horizons control centre on Tuesday as scientists celebrated the spacecraft’s dramatic flyby of Pluto, the last unexplored world in the solar system. 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 US probe shot past at more than 45,000 km/h (28,00mph) at 12.49pm BST / 7.49am ET on a trajectory that brought the fastest spacecraft ever to leave Earth within 12,500km of Pluto’s surface. The probe shot past at more than 45,000 km/h (28,000 mph) at 12.49pm BST (7.49am ET) on a trajectory that brought the fastest spacecraft ever to leave Earth’s orbit within 12,500km of Pluto’s surface.
The moment played out to the sound of The Final Countdown by the 1980s glam metal band, Europe, but the feat marked a historic achievement for the US, which can now claim to be the only nation in the world to have visited every planet in the classical solar system. 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 in the world 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.”“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”.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,” Grunsfeld said of the encounter with Pluto. “It’s been an incredible voyage.”“It’s just amazing. It’s truly a hallmark in human history,” Grunsfeld said of the encounter with Pluto. “It’s been an incredible voyage.”
Bristling with cameras and other instrumentation, 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.Bristling with cameras and other instrumentation, 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 (766,000 km) from the surface. 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 (766,000 km) from the surface.
A thin nitrogen atmosphere clings around Pluto and scientists believe that it sheds snow, with flakes tumbling down to the surface before vaporising back into the atmosphere.A thin nitrogen atmosphere clings around Pluto and scientists believe that it sheds snow, with flakes tumbling down to the surface before vaporising back into the atmosphere.
Other measurements from the probe have found that Pluto was larger than previously thought, at 2,370km across. That means it contains more ice beneath its surface and less rock than scientists had anticipated.Other measurements from the probe have found that Pluto was larger than previously thought, at 2,370km 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 4.8bn km from Earth. Instead the probe captured images and took measurements automatically and stored them on board to send back later.Mission scientists at Johns Hopkins University in Baltimore were out of contact with the spacecraft as it hurtled past the icy body 4.8bn km 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.” 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.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. 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 catasrophic failure was low, at less than one in 10,000.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 catasrophic 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.“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.
New Horizons blasted off from Earth in January 2006, carrying onboard 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.New Horizons blasted off from Earth in January 2006, carrying onboard 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 that the scientists would reconsider the name. “I call it a planet, but i’m not the rule-maker,” he said. But arguments over Pluto’s membership of the planetary club should not detract from the achievement, he added. “It should be a day of incredible pride.”In a live interview on Nasa TV on Tuesday, Charles Bolden, Nasa’s chief administrator, said he hoped that the scientists would reconsider the name. “I call it a planet, but i’m not the rule-maker,” he said. But arguments over Pluto’s membership of the planetary club should not detract from the achievement, he added. “It should be a day of incredible pride.”