Nasas Voyager 1 Spacecraft Enters Previously Unknown Layer Of The Solar System

NASA'S VOYAGER 1 SPACECRAFT ENTERS PREVIOUSLY UNKNOWN LAYER OF THE SOLAR SYSTEM SCIENTISTS * Scientists have dubbed the new region the 'magnetic highway' and say it's the last stop before interstellar space, or the space between stars * Voyager 1 and its sister probe Voyager 2 launched 35 years ago on a tour of the outer planets * The two spacecraft will run out of power by 2020 and 2025 and transmit their findings back home before shutting off for goodBy DAMIAN GHIGLIOTTY and DAMIEN GAYLEPUBLISHED: 01:32 GMT, 4 December 2012 UPDATED: 09:12 GMT, 4 December 2012NASA's long-running Voyager 1 spacecraft has entered a new layer of the solar system that scientists hadn't known was there, researchers say.Scientists have dubbed this region the 'magnetic highway' and say it's the last stop before interstellar space, or the space between stars.The discovery was announced on Monday at the American Geophysical Union meeting in San Francisco, California.SCROLL DOWN FOR VIDEOThe 'magnetic highway': Here the sun's magnetic field lines are connected to interstellar magnetic field lines, allowing particles from inside the heliosphere to zip away and particles from interstellar space to zoom in'We do believe this may be the very last layer between us and interstellar space,' said Edward Stone, Voyager project scientist based at the California Institute of Technology, in Pasadena, California.'This region was not anticipated, was not predicted.' Therefore, it's hard to determine how soon the spacecraft will leave the solar system altogether, Stone said.'It may take two months, it may take two years,' he added.The outer limits: 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 SunSpace weather: Voyager is bathed in solar wind from the southern hemisphere flowing northwardIn a release, Nasa said it was referring to this new region as a magnetic highway for charged particles because our Sun's magnetic field lines are connected there to interstellar magnetic field lines.This connection allows lower-energy charged particles from inside our heliosphere - 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.VOYAGER'S LOW-ENERGY CHARGED PARTICLE INSTRUMENTEnlarge It was data taken from Voyager's low-energy charged particle instrument that showed it first entered the magnetic highway region in July.The instrument includes a stepper motor that turns the platform on which the sensors are mounted, so that the field of view rotates through 360 degrees. This motor was tested for 500,000 steps, enough to reach the orbit of Saturn, and has now completed over 6 million steps. The old-fashioned capacitor bank underneath the motor stores energy needed to provide a 15.7-watt pulse every 192 seconds.However, because the direcrtion of the magnetic field lines has remained the same, the Voyager team believe the new region is still inside our solar bubble.They predict the direction of these magnetic field lines will change when the craft breaks out into interstellar space.'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 Dr Stone.'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 nothing.The intensity of the magnetic field also began to increase at that time.Deep in space: Voyager 1Data from two instruments aboard voyager that measure charged particles showed it first entered the magnetic highway region on July 28 this year.The region ebbed away and flowed toward Voyager 1 several times. The spacecraft entered the region again August 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, chief scientist on the low-energy charged particle instrument.'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.THE HISTORY OF VOYAGERS 1 AND 2NASA's robotic space probes Voyager 1 and 2, both weighing 1,592 lb (722 kg), prepared for launch in 1977 on missions to locate and study the outer Solar System and eventually interstellar space.Voyager 2 launched on August 20, 1977, before Voyager 1.Voyager 1 launched on September 5, 1977 moving faster than its sister probe and eventually passing it.On June 15, 2012, NASA scientists reported that Voyager 1 may be very close to entering interstellar space and becoming the first man-made object to leave the Solar System.Voyager 2 will have to be turned off by 2020. Voyager 1 will have to be turned off by 2025.'We are in a magnetic region unlike any we've been in before - about ten 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 member of the team that looks after Voyager's magnetometer.'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 its sister probe Voyager 2 launched 35 years ago on a tour of the outer planets.Voyager 2 launched on August 20, 1977, about two weeks before Voyager 1. It is now 9billion miles from the sun. Voyager 1 launched on September 5, 1977, moving faster than its sister probe and eventually passing it.It is now more than 11 billion miles from the sun. The signal from Voyager 1 takes approximately 17 hours to travel to Earth.After hurtling into space, both probes have continued to travel toward the fringes of the solar system.Interstellar missions: A map of the Voyager tours through outer spaceSaturn: an image of the sixth planet taken by Voyager 2Neptune: An image of the eight planet taken by Voyager 2The Voyagers are NASA's longest-running spacecraft, and will continue traveling after they have left the solar system.As soon as Voyager 1 breaks through to interstellar space, it will be the first man-made object to leave the solar system, Stone said.However, it would take at least 40,000 years before either probe came close to another star, Stone said.Long before that both Voyagers will run out of power and transmit their findings back home before shutting off for good.'We will have enough power for all the instruments until 2020; at that point we will have to turn off our first instrument,' Stone said.Voyager 1 will have to be turned off by 2025.NOW WATCH A VIDEO OF VOYAGER TRAVERSING THE 'MAGNETIC HIGHWAY'