Space

December 5, 2012

Voyager 1 probe encounters new region in deep space

NASA’s Voyager 1 spacecraft has entered a new region at the far reaches of our solar system that scientists feel is the final area the spacecraft has to cross before reaching interstellar space.

Scientists refer to this new region as a magnetic highway for charged particles because our sun’s magnetic field lines are connected to interstellar magnetic field lines. This connection allows lower-energy charged particles that originate from inside our heliosphere, or the bubble of charged particles the sun blows around itself, to zoom out and allows higher-energy particles from outside to stream in. Before entering this region, the charged particles bounced around in all directions, as if trapped on local roads inside the heliosphere.

The Voyager team infers this region is still inside our solar bubble because the direction of the magnetic field lines has not changed. The direction is predicted to change when Voyager breaks through to interstellar space. The new results were described at the American Geophysical Union meeting in San Francisco Dec. 3.

“Although Voyager 1 still is inside the sun’s environment, we now can taste what it’s like on the outside because the particles are zipping in and out on this magnetic highway,” said Edward Stone, Voyager project scientist based at the California Institute of Technology, Pasadena. “We believe this is the last leg of our journey to interstellar space. Our best guess is it’s likely just a few months to a couple years away. The new region isn’t what we expected, but we’ve come to expect the unexpected from Voyager.”

Since December 2004 when Voyager 1 crossed a point in space called the termination shock, the spacecraft has been exploring the heliosphere’s outer layer, called the heliosheath. In this region, the stream of charged particles from the sun known as the solar wind abruptly slowed down from supersonic speeds and became turbulent. Voyager 1’s environment was consistent for about five and a half years. The spacecraft then detected that the outward speed of the solar wind slowed to zero.

The intensity of the magnetic field also began to increase at that time.

Voyager data from two onboard instruments that measure charged particles showed the spacecraft first entered this magnetic highway region on July 28, 2012. The region ebbed away and flowed toward Voyager 1 several times. The spacecraft entered the region again Aug. 25 and the environment has been stable since.

“If we were judging by the charged particle data alone, I would have thought we were outside the heliosphere,” said Stamatios Krimigis, principal investigator of the low-energy charged particle instrument, based at the Johns Hopkins Applied Physics Laboratory, Laurel, Md. “But we need to look at what all the instruments are telling us and only time will tell whether our interpretations about this frontier are correct.”

Spacecraft data revealed the magnetic field became stronger each time Voyager entered the highway region; however, the direction of the magnetic field lines did not change.

“We are in a magnetic region unlike any we’ve been in before – about 10 times more intense than before the termination shock – but the magnetic field data show no indication we’re in interstellar space,” said Leonard Burlaga, a Voyager magnetometer team member based at NASA’s Goddard Space Flight Center in Greenbelt, Md. “The magnetic field data turned out to be the key to pinpointing when we crossed the termination shock. And we expect these data will tell us when we first reach interstellar space.”

Voyager 1 and 2 were launched 16 days apart in 1977 and at least one of the spacecraft visited Jupiter, Saturn, Uranus and Neptune. Voyager 1 is the most distant human-made object, about 11 billion miles (18 billion kilometers) away from the sun. The signal from Voyager 1 takes approximately 17 hours to travel to Earth. Voyager 2, the longest continuously operated spacecraft, is about 9 billion miles (15 billion kilometers) away from our sun. While Voyager 2 has seen changes similar to those seen by Voyager 1, the changes are much more gradual. Scientists do not think Voyager 2 has reached the magnetic highway.

The Voyager spacecraft were built and continue to be operated by NASA’s Jet Propulsion Laboratory, in Pasadena, Calif. The Voyager missions are a part of NASA’s Heliophysics System Observatory, sponsored by the Heliophysics Division of the Science Mission Directorate in NASA Headquarters in Washington.

 

For more information about the Voyager spacecraft, visit http://www.nasa.gov/voyager.

 




All of this week's top headlines to your email every Friday.


 
 

 

Headlines August 28, 2015

Business: Rafale, Mistral on agenda for Le Drian in Malaysia, India¬†– French Defense Minister Jean-Yves Le Drian is due to visit Malaysia Aug. 30, with talks expected to cover the Rafale fighter jet and Mistral helicopter carrier, website La Tribune reported. U.S. Army to choose new landing craft next year¬†– In line with the Pentagon’s...
 
 

News Briefs August 28, 2015

Boeing plans to lay off some Southern California workers Boeing has announced that it plans to lay off employees at its Southern California-based satellite division. The Los Angeles Times reports that the aerospace giant said Aug. 25 that it will lay off as many as several hundred employees at the El Segundo factory. Boeing says...
 
 

Special tactics Airmen killed in hostile incident

Two special tactics airmen, who were deployed in support of Operation Freedom’s Sentinel, were killed near Camp Antonik, Afghanistan, Aug. 26. Capt. Matthew D. Roland, 27, and SSgt. Forrest B. Sibley, 31, were at a vehicle checkpoint when two individuals wearing Afghan National Defense and Security Forces uniforms opened fire on them. NATO service members...
 

 

Hurricane Hunters to fly Tropical Storm Erika

The Air Force Reserve Hurricane Hunters are operating out of Homestead Air Reserve Base, Fla., flying their state-of-the-art WC-130J Super Hercules into Tropical Storm Erika in support of the National Hurricane Center in Miami. The 53rd Weather Reconnaissance Squadron flew four missions into the tropical storm from their deployed location at St. Croix in the...
 
 
LM-MUOS

U.S. Navy, Lockheed Martin ready to launch MUOS-4 Aug. 31

The U.S. Navy and Lockheed Martin are ready to launch the fourth Mobile User Objective System secure communications satellite, MUOS-4, from Cape Canaveral Air Force Station, Fla., Aug. 31 aboard a United Launch Alliance Atlas V...
 
 

Pentagon probing alleged distorting of war intelligence

The Pentagon’s inspector general is investigating an allegation that the military command overseeing the anti-Islamic State campaign distorted or altered intelligence assessments to exaggerate progress against the militant group, a defense official said Aug. 26. The official was not authorized to discuss the probe publicly and so spoke on condition of anonymity. The investigation was...
 




0 Comments


Be the first to comment!


Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>