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New Horizons Pluto probe makes contact with Earth New Horizons Pluto probe makes contact with Earth
(about 3 hours later)
Nasa’s New Horizons spacecraft has made contact with Earth in a dramatic indication that it has survived its flypast of the tiny planet Pluto. Nasa’s New Horizons spacecraft has made contact with Earth, confirming its successful flypast of Pluto, after a journey to the far reaches of the solar system that has taken nine-and-a-half years and 3 billion miles (4.88bn km).
About 13 hours after its closest approach to Pluto, the last major unexplored body in the solar system, the probe “phoned home”, signalling that it remained unscathed following its 31,000 miles per hour (50,000km/h) blitz through the Pluto system.
The signal capped a journey of three billion miles (4.8bn km) that began nine-and-a-half years ago.
Related: Pluto flyby: New Horizons probe makes contact with Earth – liveRelated: Pluto flyby: New Horizons probe makes contact with Earth – live
New Horizons spacecraft had passed by the ice-and-rock planetoid and its entourage of five moons at 7.49am EDT (11.49 GMT) on Tuesday. But the confirmation signal was only received by Nasa at abut 9pm EDT. At precisely 8.52.37pm Eastern US time, the probe “phoned home” to mission control in Maryland, 13 hours after it flew within 7,750 miles (12,472km) of Pluto.
The contact with flight controllers at the Johns Hopkins University Applied Physics Lab outside Baltimore, sparking a wave of shouts and applause from the crowd gathered to watch the drama unfold. Scientists greeted the news of its safe passage with cheers and tears, calling it a historic day for space exploration.
The successful mission means humans – specifically, the US – have now reached all nine planets of our solar system. Although Pluto was reclassified as a dwarf planet in 2006 – just months after New Horizons set off on its mission – Charles Bolden, Nasa’s chief administrator, said he hoped that decision would be reconsidered.
The New Horizons spacecraft had passed by Pluto and its five moons at 7.49am EDT (12.49 BST/9.49pm AEST) on Tuesday. It spent the following eight hours continuing to collect data and images from the last major unexplored body in the universe, before sending out its signal home.
The contact with flight controllers at the Johns Hopkins University applied physics lab in Maryland, some four-and-a-half hours later, sparked a wave of shouts and applause from the crowd gathered to watch the historic moment unfold.
Alice Bowman, the mission operations manager, said no errors or problems with the probe had been recorded: “We have a healthy spacecraft. We’ve recorded data of Pluto’s system and we’re outbound from Pluto … Just like we practised, just like we planned it. We did it.”
Managers had estimated there was a one in 10,000 chance a debris strike could destroy the probe as it soared just 7,750 miles (12,472km) – about the distance from New York to Mumbai – from Pluto.Managers had estimated there was a one in 10,000 chance a debris strike could destroy the probe as it soared just 7,750 miles (12,472km) – about the distance from New York to Mumbai – from Pluto.
With 99% of the data gathered during the encounter still on the spaceship, New Horizons’ survival was critical to the mission.With 99% of the data gathered during the encounter still on the spaceship, New Horizons’ survival was critical to the mission.
Bowman said she had had concerns before the signal was received. “You have a lot of faith in your children, but sometimes they don’t do exactly what you want them to do … so you worry. But our spacecraft did exactly what it was supposed to do and the signal was there.”
“This is truly a hallmark in human history,” said John Grunsfeld, Nasa’s associate administrator for science.“This is truly a hallmark in human history,” said John Grunsfeld, Nasa’s associate administrator for science.
New Horizons spent more than eight hours after its closest approach looking back at Pluto for a series of experiments to study the planet’s atmosphere and photograph its night-side using light reflected off its primary moon Charon. US president Barack Obama tweeted in praise of the mission, calling it “a great day for discovery and American leadership”.
Sending back its first post-flyby signal took another four-and-a-half hours, the time it takes radio signals, travelling at light speed, to travel the three billion miles (4.8bn km) back to Earth. Since contact was re-established, so far only engineering data has been downloaded.
Already, the trickle of images and measurements relayed from New Horizons before Tuesday’s pass by Pluto has changed scientists’ understanding of this diminutive world, which is smaller than Earth’s moon. But from early Wednesday morning US time (5.50am ET/10.50am BST/7.50pm AEST), scientific data will begin to be transferred to mission control. This will bring fresh images of Pluto – at 10 times the resolution of even the best pictures so far seen – as well as a wealth of information on the planet, as well as the moon Charon and its other satellites.
These will be unveiled at a press conference later on Wednesday.
Already, the images and measurements relayed from New Horizons has changed scientists’ understanding of Pluto, which is smaller than Earth’s moon.
Once considered an icy, dead world, the planetoid has yielded signs of geological activity, with evidence of past and possibly present-day tectonics, or movements of its crust.Once considered an icy, dead world, the planetoid has yielded signs of geological activity, with evidence of past and possibly present-day tectonics, or movements of its crust.
“This is clearly a world where both geology and atmosphere climatology play a role,” said Alan Stern, New Horizons’ lead scientist, with the Southwest Research Institute in Boulder, Colorado. He noted that it appears that nitrogen and methane snow fall on Pluto.“This is clearly a world where both geology and atmosphere climatology play a role,” said Alan Stern, New Horizons’ lead scientist, with the Southwest Research Institute in Boulder, Colorado. He noted that it appears that nitrogen and methane snow fall on Pluto.
Pluto circles the sun every 248 years in a highly tilted orbit that creates radical changes from season to season. Pluto travels closer to the sun than the orbit of Neptune before it cycles back into the solar system’s deep freeze more than 40 times farther away than Earth.
Scientists have many questions about Pluto, which was still considered the solar system’s ninth planet when New Horizons was launched in 2006. Pluto was reclassified as a “dwarf planet” after the discovery of other Pluto-like spheres orbiting in the Kuiper Belt, the region beyond the eighth planet, Neptune. The objects are believed to be remnants from the formation of the solar system 4.6bn years ago.
“Now the solar system will be further opened up to us, revealing the secrets of distant Pluto,” British cosmologist Stephen Hawking said in a message broadcast on Nasa TV.“Now the solar system will be further opened up to us, revealing the secrets of distant Pluto,” British cosmologist Stephen Hawking said in a message broadcast on Nasa TV.
“We explore because we are human and we want to know. I hope that Pluto will help us on that journey,” Hawking said.“We explore because we are human and we want to know. I hope that Pluto will help us on that journey,” Hawking said.
It will take about 16 months for New Horizons to transmit back all the thousands of images and measurements taken during its pass by Pluto. By then, the spacecraft will have travelled even deeper into the Kuiper Belt, heading for a possible follow-on mission to one of Pluto’s cousins.It will take about 16 months for New Horizons to transmit back all the thousands of images and measurements taken during its pass by Pluto. By then, the spacecraft will have travelled even deeper into the Kuiper Belt, heading for a possible follow-on mission to one of Pluto’s cousins.
Reuters contributed to this report