Signs changing fast for Voyager at solar system edge

August 3, 2012, JPL/NASA
This artist's concept shows NASA's two Voyager spacecraft exploring a turbulent region of space known as the heliosheath, the outer shell of the bubble of charged particles around our sun. Image credit: NASA/JPL-Caltech

( -- Two of three key signs of changes expected to occur at the boundary of interstellar space have changed faster than at any other time in the last seven years, according to new data from NASA's Voyager 1 spacecraft.

For the last seven years, 1 has been exploring the outer layer of the bubble of charged particles the sun blows around itself. In one day, on July 28, data from Voyager 1's cosmic ray instrument showed the level of high-energy originating from outside our solar system jumped by five percent. During the last half of that same day, the level of lower- originating from inside our solar system dropped by half. However, in three days, the levels had recovered to near their previous levels.

A third key sign is the direction of the magnetic field, and scientists are eagerly analyzing the data to see whether that has, indeed, changed direction. Scientists expect that all three of these signs will have changed when Voyager 1 has crossed into interstellar space. A preliminary analysis of the latest magnetic field data is expected to be available in the next month.

"These are thrilling times for the Voyager team as we try to understand the quickening pace of changes as Voyager 1 approaches the edge of interstellar space," said Edward Stone, the Voyager project scientist based at the California Institute of Technology, Pasadena, Calif. "We are certainly in a new region at the edge of the solar system where things are changing rapidly. But we are not yet able to say that Voyager 1 has entered interstellar space."

The levels of high-energy have been increasing for years, but more slowly than they are now. The last jump -- of five percent -- took one week in May. The levels of lower-energy particles from inside our have been slowly decreasing for the last two years. Scientists expect that the lower-energy particles will drop close to zero when Voyager 1 finally crosses into interstellar space.

"The increase and the decrease are sharper than we've seen before, but that's also what we said about the May data," Stone said. "The data are changing in ways that we didn't expect, but Voyager has always surprised us with new discoveries."

Voyager 1, which launched on Sept. 5, 1977, is 11 billion miles (18 billion kilometers) from the sun. Voyager 2, which launched on Aug. 20, 1977, is close behind, at 9.3 billion miles (15 billion kilometers) from the sun.

"Our two veteran Voyager spacecraft are hale and healthy as they near the 35th anniversary of their launch," said Suzanne Dodd, Voyager project manager based at 's Jet Propulsion Laboratory, Pasadena. "We know they will cross into . It's just a question of when."

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3.8 / 5 (26) Aug 03, 2012
"Our two veteran Voyager spacecraft are hale and healthy as they near the 35th anniversary of their launch,"

Kudos NASA and JPL, you sure got our money's worth out of those two.
4.7 / 5 (13) Aug 03, 2012
I remember the excitement that the Voyagers created during their "Grand Tour" of the Solar System. Truly those craft have proven themselves to be among NASA's greatest achievements.
3.5 / 5 (15) Aug 03, 2012
I just love science & scientific endeavor.

When I was 5 years old I told my Dad one night standing in the backyard beneath a sky blanketed with stars, that I wanted to be a scientist when I grow up. I grew up, I'm a scientist/engineer, I admire my colleagues who have worked so hard to give me knowledge about our Universe that I just don't have enough available time in one lifetime to indulge in.

Thank you so much Voyager team for decades of dedication, all the hats I own are off to you, and none of them are "tin-foil".
3.2 / 5 (9) Aug 03, 2012
Great work NASA. I hope the Mars Science Laboratory does half as well Sunday night.
5 / 5 (6) Aug 03, 2012
I for one will definitely be watching when the Mars Curiosity lands at 1:30am EST Monday morning. If NASA can just pull off that amazing landing sequence... the complexity is unbelievable. Here's hoping they "stick" the landing - at under 2 mph of course - and we should have video of the landing as well. The Voyager has been part of the science discussion for almost 35 years now and here's hoping for at least 10 more.
1.4 / 5 (11) Aug 03, 2012
Andrew L. Gasser launched Tea Party In Space in June as a way to bring fiscal responsibility into the space program, he told TPM Tuesday. He called the group, which was formed in conjunction with the South Florida Tea Party, the first issue-specific tea party in the country.

Gasser explained that the group aims to bring the free markets into the space program, because right now, he say, there is only the government which amounts to socialism. It is socialism when you have the government coming down and saying, this is what we want to build, and this is how we want you to build it, he said.
1.3 / 5 (12) Aug 04, 2012
and he was so right, Darling. Let's have a tea party, just you and me.
1.3 / 5 (12) Aug 04, 2012
Whoops. I didn't mean you, Vendi. Sorry about that. I was talking to someone else.
1.4 / 5 (11) Aug 04, 2012
"Our two veteran Voyager spacecraft are hale and healthy as they near the 35th anniversary of their launch,"

Kudos NASA and JPL, you sure got our money's worth out of those two.

Nothing like building with cast iron and plutonium.
1 / 5 (2) Aug 04, 2012
"Our two veteran Voyager spacecraft are hale and healthy as they near the 35th anniversary of their launch,"

Kudos NASA and JPL, you sure got our money's worth out of those two.

Nothing like building with cast iron and plutonium.

That's right, shooty-

Mission conditions and objectives dictate equipment construction materials. Papier-mache and AAs probably wouldn't have held up very well in an operating environment of near-zero temperatures, constant hard radiation and the continual bombardment of micrometeorites.

The selection of materials wasn't then --nor is it now-- an example of "sledgehammer" technology.

That being said, however --I do agree with you that, for precisely that reason, it is grounds for a Caveman-style admiration. Not a bad thing.
4 / 5 (1) Aug 05, 2012
A very rare discussion thread, where all comments got only a 5. Amd then it was tea time...
1 / 5 (5) Aug 06, 2012
I once asked a NASA friend why we don't have cars that are that well built. His reply was that I could, if I were willing to pay several million dollars for it.
1 / 5 (7) Aug 06, 2012
Sub: Change in orientation
Plasma Regulated Electromagnetic Phenomena in magnetic Field Environment- cosmology Vedas Interlinks -provide critical orientation modes.Please provide more Specific information -voyager I and Voyager II- with reference Sun.
not rated yet Aug 06, 2012
Tremendously exciting. And the interest in the Curiosity landing on Mars last night was so strong that most of the NASA websites live streaming the event were overwhelmed. That bodes well for the future of science, if we can keep from blowing ourselves up, of course....

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