After five-year trip, Juno enters Jupiter’s orbit

July 5: Ducking through intense belts of violent radiation as it skimmed over the clouds of Jupiter at 130,000 miles per hour, NASA’s Juno spacecraft finally clinched its spot on Monday in the orbit of the solar system’s largest planet.

It took five years for Juno to travel this far on its $1.1 billion mission, and the moment was one that NASA scientists and space enthusiasts had eagerly — and anxiously — anticipated.

At 11:53 pm, Easter n time, a signal from the spacecraft announced the end of a 35minute engine burn that left it in the grip of its desired orbit around Jupiter. Cheers and clapping erupted at the mission operations centre at NASA’s Jet Propulsion Laboratory, in Pasadena, California, which is managing Juno.

“This is the hardest thing NASA has ever done,” Scott Bolton, Juno’s principal investigator, told the mission team a few minutes later. “That’s my claim.”

Status messages for each maneuver of the spacecraft came in as expected. The length of the engine firing turned out to be within one second of what had been predicted.

Diane Brown, the programme executive for Juno at NASA headquarters, described the performance as flawless.

“To know we can all go to bed tonight, not worrying about what’s going to happen tomorrow, it’s pretty awesome,” she said at a news conference.

Rick Nybakken, Juno’s project manager, held up a sheaf of papers as he celebrated the smooth execution of the maneuver.

“We prepared a contingency communications procedure, and guess what?” he said, ripping the papers. “We don’t need that anymore.”

Juno is just the second spacecraft to enter orbit around Jupiter. NASA’s Galileospacecraftspenteight years there surveying the planet and its many moons. But except for a probe that parachuted into Jupiter’s atmosphere, Galileo did not have the tools that Juno does todelveintowhatliesbeneath Jupiter’s clouds.

“We have a chance with Juno to go back and study the planet in its own right,” JamesLGreen,thedirectorof planetary science at NASA, said during a news conference earlier on Monday.

Jupiter, most likely the first planet formed after the sun, is believed to hold the keys to understanding the origins of our solar system. How much water it contains and the possible presence of a rocky core could reveal where in the solar system Jupiter was created and provide clues to the early days of other planets.

Juno’s instruments are designed to precisely measure the magnetic and gravitational fields of Jupiter and the glow of microwaves emanating from within. That, for instance, will give hints about stor m systems like the visible Great Red Spot, which has persisted for centuries, although it has been shrinking.

“Juno is really searching for some hints about our beginnings, how everything started,” Dr Bolton said. “But these secrets are pretty well guarded by Jupiter.” NYT

Nasa scientists said at a news conference on Monday that a signal from the spacecraft Juno confirmed that it had arrived at Jupiter