Juno's Jupiter mission a quest to find 'recipe for planet-making'

Even for scientists versed in the grand scale of astronomy, it's never been easy to grasp the scope of Jupiter.

After all, you could fit every piece of the solar system other than the sun inside Jupiter - all the other planets, moons and asteroids - with plenty of room to spare. Jupiter has cannibalized 20 moons over the years and still has at least 63, one bigger than Mercury. Jupiter's "spot" is actually a hurricane, which has lasted for hundreds of years and is more than twice the diameter of Earth.

But Jupiter isn't just a forbidding ball of gas. Somewhere in there are the clues, scientists believe, to the origin of the solar system - and Earth. Starting the morning of Aug. 5, NASA will enter the launch period for the spacecraft Juno, which will begin an unprecedented exploration of Jupiter's profound secrets.

"We are after the recipe for planet-making. To get the list of ingredients - this is the place," said Scott Bolton, the mission's principal investigator and the director of at San Antonio's Southwest Research Institute.

Roughly four and a half billion years ago, the sun formed when a giant cloud of gas and dust collapsed under its own gravity. The sun sucked up virtually all of it, but there were leftovers. Those leftovers formed the solar system, and most of them wound up inside Jupiter.

Unlike other planets that shed their elements over time and undergo sweeping change, Jupiter's sheer girth has allowed it to retain most of its original features. Contained inside, said William Hubbard, a University of Arizona professor of planetary sciences and one of the mission's top scientists, is a record, essentially, of the birth of the planets.

"It ties right back to us," Bolton said. "These are the elements of life, the elements that Earth is made out of. How Jupiter managed to get enriched in these elements is right at the essence of how we got here. Where did we come from? That's what it comes down to."

Juno can launch any time during a 22-day period, hitching a ride on an Atlas V rocket from Cape Canaveral in Florida.

Juno's solar panels, configured like three spokes of a Ferris wheel, will supply power to the craft as it journeys across 1.8 billion miles of space. The trip will take five years. By the fall of 2017, Juno is expected to have completed 34 elliptical, polar orbits around Jupiter. Its task complete, Juno will then be plunged, in a final hurrah, into Jupiter's depths, where it will disintegrate.

The Jet Propulsion Laboratory in La Canada Flintridge, Calif., is managing the $1.1 billion mission.

With the recent end of the space shuttle program, NASA has faced questions about an approach to manned space exploration that critics have called aimless. On the other hand, this year marks a bustling period in unmanned exploration, particularly on deep-space missions.

Juno's launch will follow NASA's Dawn spacecraft arriving into orbit around the protoplanet Vesta, the first prolonged encounter with an object in the main belt between Mars and Jupiter.

In September, twin spacecraft will lift off to fly in coordinated orbits around the moon. That project is expected to yield the most complete gravitational map of the moon and also help scientists understand the origins of the Earth.

Also this fall, the new Mars rover, Curiosity, is scheduled to launch from Cape Canaveral, and is expected to continue the search for water and evidence of life.

"In all the time I've been working, I can't think of one time that has had so many launches, so fast," said Bolton, who was a scientist at JPL from 1980 until 2005. "It's an exciting time."

Juno's orbits have been spaced with precision to cover the entire planet. The result, scientists believe, will be the first comprehensive mapping of Jupiter's gravitational and magnetic fields.

Scientists will also be able to determine whether there is a solid core underneath Jupiter's massive bands of gas. That discovery will help to reveal the timeline of the formation of the solar system.

If Jupiter has no core, then it probably formed as the sun did - by inhaling, in a sense, during a gravitational instability. If Jupiter does have a solid core, then its rocky elements would have needed time to form before being surrounded by the bands of gas that circle the planet.

Despite those potential leaps - and though scientists have dreamed of studying Jupiter at this level of detail since the 1970s - Juno was, for many years, not a sure thing.

Spacecraft dating back to Pioneer 10 in the early 1970s have studied Jupiter, "but just kind of looking out the car window," said Jan Chodas, a JPL engineer and the Juno project manager. Jupiter's hostile environment, particularly its crippling doses of radiation, was an impediment.

Juno, too, will be subjected to an enormous amount of radiation - the equivalent of 100 million dental X-rays. That level of radiation can fry a spacecraft's electronics in an instant, and was among the reasons that Jupiter missions were initially passed over in competitions to obtain launch approval.

Then, in the late 1990s, Bolton was working on Cassini-Huygens, the first spacecraft to go into orbit around Saturn.

One morning - after spending the previous day in a series of meetings about measuring radiation in deep space - Bolton was standing in the shower. He had an epiphany.

He would need a specific instrument loaded onto Juno - a microwave radiometer, which could probe the planet's atmosphere with less interference. The spacecraft would also need to orbit Jupiter's poles, not its equator, thereby reducing the information "noise" that would come from the planet's radiation belts.

The combination, he believed, would yield the first solid reading of water and oxygen on Jupiter. It would be a critical step in understanding the distribution of heavy elements during the formation of the planets. There would be implications far beyond our ; hundreds of "Jupiter-class" planets have been discovered in recent years in further reaches of the galaxy.

"The rest is history," Bolton said.

To complete such a promising and demanding set of calculations during its orbits, Juno will fly little more than 3,000 miles above Jupiter's poles, far closer than any spacecraft has ever managed.

Engineers have equipped it with a protective titanium box, 500 pounds and roughly three square feet, to shield what engineers call Juno's brain and heart - its data components and the electronics that control its power and send its science back to Earth. Chodas said is essentially "an armored car in space."

"Now we just have to wait five years until we get to Jupiter," Bolton said. "You have to have a lot of patience in this business."

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NASA Prepares for New Juno Mission to Jupiter

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User comments

Jul 28, 2011
I am happy to read all these stories about the great future of space exploration!

But frankly, I do not believe the story.

Western economies today face the consequences of decades of deceptive information about global warming induced by the release of CO2 by our once thriving industries:



The future of space exploration was traded away to gain favor with politicians that controlled research funds and wanted to use science as a tool of propaganda.

What a sad, sad day for science!

Jul 28, 2011
Here you go Oliver, something to gladden your heart.

"New NASA Data Blow Gaping Hole In Global Warming Alarmism"

Jul 28, 2011
ugh, how many times can they say alarmist in that news article. sounds so bias.

Jul 29, 2011
Shootist, you cite an article by Forbes magazine, home of the well known right-wing billionaire propagandist, and pretend that its a NASA press release. Nice try.

Jul 29, 2011
If Jupiter has no core, then it probably formed as the sun did - by inhaling, in a sense, during a gravitational instability. If Jupiter does have a solid core, then its rocky elements would have needed time to form before being surrounded by the bands of gas that circle the planet.

Wonder what they mean by no core? That would be imposible. Even if Jupiter started as a ball of Hydrogen (impossible) it has acquired many asteroids etc over the years and since these things are not hydrogen or helium there would have to be a solid core.

Unless you can say molten rock is not a core in which case Earth does not have a core either.

Jul 29, 2011
If Jupiter has no core, then it probably formed as the sun did - by inhaling, in a sense, during a gravitational instability.

Wonder what they mean by no core?

They mean that Jupiter formed the way they thought the Sun formed.

The Sun actually formed on the supernova core.

Jupiter formed our of H, He, C, N from the outer layer of the supernova.



1. "Strange xenon, extinct super-heavy elements, and
the solar neutrino puzzle", Science 195, 208-209 (1977);


2. "Isotopes of tellurium, xenon and krypton in the
Allende meteorite retain record of nucleosynthesis",
Nature 277, 615-620 (1979)


With kind regards,
Oliver K. Manuel

Jul 29, 2011
Here you go Oliver, something to gladden your heart.

"New NASA Data Blow Gaping Hole In Global Warming Alarmism"

A paper written by Roy Spencer, a proponent of Intelligent Design. How classy.

Aug 01, 2011
The Sun actually formed on the supernova core.
I thought(well, in fact i know) you said that the supernova neutron star core IS our sun and the outer layers of the sun are waste products from neutron repulsion. Oliver, you have no place to talk when it conmes to credibility of scientists and your saying they are all lying and its some massive plot. You lied your whole life about molesting your children and cant back up your theory if anyone asks you to explain something and then just repeat the same garbage you always do we've all read before w/o actually addressing the question while claiming you did answer it. Your credibility is shit mr manuel.

Aug 03, 2011
jsdarkdestruction... Looks like you have rise lots of money on false researches on "hydrogen helium ball". You are sleeping badly, thinking on neutron star system - Sun. There are lots of similar falsifiers in the NASA and other scientific organizations, especially on BBT. You don't know even the alimentary nuclear laws. who is paying money to you. give me your address. I will send protest.

Aug 05, 2011
Bullshit, for 1 how much i make is none of your business, but its not very much at all and for 2 your conspiracy theory is laughable and also alarming though, you like oliver need to check in to your local psych ward asap!

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