[AbraxiaAsus]

JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION





PASADENA, Calif. - Earlier today, navigators and mission controllers for NASA's Juno mission to Jupiter watched their computer screens as their spacecraft successfully performed its first deep-space maneuver. This first firing of Juno's main engine is one of two planned to refine the spacecraft's trajectory, setting the stage for a gravity assist from a flyby of Earth on Oct 9, 2013. Juno will arrive at Jupiter on July 4, 2016.

The deep-space maneuver began at 6:57 p.m. EDT (3:57 p.m. PDT) today, when the Leros-1b main engine was fired for 29 minutes 39 seconds. Based on telemetry, the Juno project team believes the burn was accurate, changing the spacecraft's velocity by about 770 mph (344 meters a second) while consuming about 829 pounds (376 kilograms) of fuel.

"This first and successful main engine burn is the payoff for a lot of hard work and planning by the operations team," said Juno Project Manager Rick Nybakken of NASA's Jet Propulsion Laboratory in Pasadena, Calif. "We started detailed preparations for this maneuver earlier this year, and over the last five months we've been characterizing and configuring the spacecraft, primarily in the propulsion and thermal systems. Over the last two weeks, we have carried out planned events almost every day, including heating tanks, configuring subsystems, uplinking new sequences, turning off the instruments and increasing the spacecraft's spin rate. There is a lot that goes into a main engine burn."

The burn occurred when Juno was more than 300 million miles (483 million kilometers) away from Earth.

A second deep space maneuver, of comparable duration and velocity change, is planned for Sept. 4. Together, they will place Juno on course for its Earth flyby, which will occur as the spacecraft is completing one elliptical orbit around the sun. The Earth flyby will boost Juno's velocity by 16,330 mph (about 7.3 kilometers per second), placing the spacecraft on its final flight path for Jupiter. The closest approach to Earth, on Oct. 9, 2013, will occur when Juno is at an altitude of about 310 miles (500 kilometers).

"We still have the Earth flyby and another 1.4 billion miles and four years to go to get to Jupiter," said Scott Bolton, Juno's principal investigator from the Southwest Research Institute in San Antonio. "The team will be busy during that whole time, collecting science on the way out to Jupiter and getting ready for our prime mission at Jupiter, which is focused on learning the history of how our solar system was formed. We need to go to Jupiter to learn our history because Jupiter is the largest of the planets, and it formed by grabbing most of the material left over from the sun's formation. Earth and the other planets are really made from the leftovers of the leftovers, so if we want to learn about the history of the elements that made Earth and life, we need to first understand what happened when Jupiter formed."

Juno was launched on Aug. 5, 2011. Once in orbit, the spacecraft will circle Jupiter 33 times, from pole-to-pole, and use its collection of eight science instruments to probe beneath the gas giant's obscuring cloud cover. Juno's science team will learn about Jupiter's origins, structure, atmosphere and magnetosphere, and look for a potential solid planetary core. Juno's name comes from Greek and Roman mythology. The god Jupiter drew a veil of clouds around himself to hide his mischief, and his wife, the goddess Juno, was able to peer through the clouds and reveal Jupiter's true nature.

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Juno mission for the principal investigator, Scott Bolton, of Southwest Research Institute in San Antonio. The Juno mission is part of the New Frontiers Program managed at NASA's Marshall Space Flight Center in Huntsville, Ala. Lockheed Martin Space Systems, Denver, built the spacecraft. JPL is a division of the California Institute of Technology in Pasadena.

More information about Juno is online at http://www.nasa.gov/juno and http://missionjuno.swri.edu .

-end-

[Aswdwdfg]

> setting the stage for a gravity assist from a flyby of Earth on Oct 9, 2013

That's correct, Juno hasn't reached Earth yet.

Multiple flybys are not necessary from a speed point of view, only from a fuel load point of view. It's a cost-cutting measure. I hope, sincerely hope without much chance of it happening, that Juno will take photographs of the rings of satellites and space debris orbiting the Earth. I'm hoping that they will be able to observe real natural dust rings - Earth is the largest planet in the solar system for which rings have not yet been found. To see them would require looking at the Earth from well beyond the orbit of the Moon but far closer than the orbit of Mars (Earth atmosphere noise swamps any ground-based observations), so deep space probes during flyby are the only ways to see them - if they exist.

[Breeriacoirl]

I'm hoping that they will be able to observe real natural dust rings - Earth is the largest planet in the solar system for which rings have not yet been found.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> >>>

Interesting concept. Never actually have given much thought to the Earth with rings.

[Mowselelew]

I hope, sincerely hope without much chance of it happening, that Juno will take photographs of the rings of satellites and space debris orbiting the Earth. I'm hoping that they will be able to observe real natural dust rings - Earth is the largest planet in the solar system for which rings have not yet been found. To see them would require looking at the Earth from well beyond the orbit of the Moon but far closer than the orbit of Mars (Earth atmosphere noise swamps any ground-based observations), so deep space probes during flyby are the only ways to see them - if they exist.

Would be a little surprising if there were only ionized particles trapped in the Van-Allen Belts.

[soonahonsefalh]

Would be a little surprising if there were only ionized particles trapped in the Van-Allen Belts. isn't that what the VAB are? Ionised particles?

[EzekelEnzino]

isn't that what the VAB are? Ionised particles?

I believe so, but would non-ionized particles be excluded from these zones?

[toreesi]

i would imagine a tendency for that but like anything there would be a certain proportion of unionised particles.

[Todilrdc]

Strange that nobody seems to be looking for Earth rings. At least one or two questions could be answered were there something in the immediate neighborhood to study.

[dr-eavealer]

what i meant in my first comment is that the belts are the charged particles.

[seatlyled]

what i meant in my first comment is that the belts are the charged particles.

I see your point. My head is a bit stuffy. Not so good for speculating with.

[Poreponko]

i had that cold a few weeks ago. you do recover.

[AndyScouchek]

i had that cold a few weeks ago. you do recover.

I had a 2 month flu that gave up a few weeks ago. Am glad this feels more like a cold. Seems to be a bit of a competition between the kids and the adults who can run up more medical bills round here this year.

[kasandrasikl]

I hope, sincerely hope without much chance of it happening, that Juno will take photographs of the rings of satellites and space debris orbiting the Earth. I'm hoping that they will be able to observe real natural dust rings - Earth is the largest planet in the solar system for which rings have not yet been found. To see them would require looking at the Earth from well beyond the orbit of the Moon but far closer than the orbit of Mars (Earth atmosphere noise swamps any ground-based observations), so deep space probes during flyby are the only ways to see them - if they exist.

It seems most logical to assume that the moons passage from it's original orbit to it's current one would have swept any ring materials up. If there is something there now, it would have to be associated with fluctuations in the outer Van-Allen belt.