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Voyager approaching solar system's outer limits NASA NEWS RELEASE Posted: November 5, 2003 NASA's Voyager 1 spacecraft is about to make history again. It is the first spacecraft to enter the solar system's final frontier, a vast expanse where wind from the sun blows hot against thin gas between the stars: interstellar space. However, before it reaches this region, Voyager 1 must pass through the termination shock, a violent zone that is the source of beams of high-energy particles. Voyager's journey through this turbulent zone will give scientists the first direct measurements of our solar system's unexplored final frontier, the heliosheath. Scientists are debating if this passage has already begun. Two papers about this research are being published in Nature today.
"Voyager 1 has seen striking signs of the region deep in space where a giant shock wave forms, as the wind from the sun abruptly slows and presses outward against the interstellar wind. The observations surprised and puzzled us, so there is much to be discovered as it begins exploring this new region at the outer edge of the solar system," said Dr. Edward Stone, Voyager Project Scientist, California Institute of Technology, Pasadena, Calif. Launched on September 5, 1977, Voyager explored the giant planets Jupiter and Saturn before being tossed out toward deep space by Saturn's gravity. It is approaching, and may have temporarily entered, the region beyond termination shock. At more than eight billion miles from the sun, Voyager 1 is the most distant object from Earth built by humanity. The termination shock is where the solar wind, a thin stream of electrically charged gas blown constantly from the sun, is slowed by pressure from gas between the stars. At the termination shock, the solar wind slows abruptly from its average speed of 700,000 to 1,500,000 mph. Estimating the location of the termination shock is hard, because we don't know the precise conditions in interstellar space. We do know speed and pressure of the solar wind changes, which causes the termination shock to expand, contract and ripple. From about August 1, 2002, to February 5, 2003, scientists noticed unusual readings from the two energetic-particle instruments on Voyager 1, indicating it had entered a region of the solar system unlike any previously encountered. This led some to claim Voyager 1 may have entered a transitory feature of the termination shock.
"We have used an indirect technique to show the solar wind slowed down from about 700,000 mph to much less than 100,000 mph. We used this same technique when the instrument measuring the solar wind speed was still working. The agreement between the two measurements was better than 20 percent in most cases," Krimigis said. "The analysis of the Voyager 1 magnetic field observations in late 2002 indicate that it did not enter a new region of the distant heliosphere by having crossed the termination shock. Rather, the magnetic field data had the characteristics to be expected based upon many years of previous observations, although the intensity of energetic particles observed is unusually high," Burlaga said. The Voyager spacecraft were built and are operated by JPL. The Voyagers were equipped with three radioisotope thermoelectric generators to produce electrical power for the spacecrafts' systems and instruments. Steadily operating for 26 years, the Voyagers owe their longevity to these generators, which produce electricity from the heat generated by the natural decay of plutonium dioxide.
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Exploring Mars Astronomy Now is pleased to announce the publication of Exploring Mars. The very best images of Mars taken by orbiting spacecraft and NASA's Spirit and Opportunity rovers fill up the 98 glossy pages of this special edition!U.S. - U.K. - E.U. - Worldwide Mars Rover mission patch A mission patch featuring NASA's Mars Exploration Rover is now available from the Astronomy Now Store.U.S. - U.K. - E.U. - Worldwide Columbia Report A reproduction of the official accident investigation report into the loss of the space shuttle Columbia and its crew of seven. U.S. - U.K. - E.U. - Worldwide Mars Panorama DISCOUNTED! This 360 degree image was taken by the Mars Pathfinder, which landed on the Red Planet in July 1997. The Sojourner Rover is visible in the image. U.S. Apollo 11 Mission Report Apollo 11 - The NASA Mission Reports Vol. 3 is the first comprehensive study of man's first mission to another world is revealed in all of its startling complexity. Includes DVD!U.S. - U.K. - E.U. - Worldwide Rocket DVD If you've ever watched a launch from Kennedy Space Center, Cape Canaveral, Vandenberg Air Force Base or even Kodiak Island Alaska, there's no better way to describe what you witnessed than with this DVD.U.S. - U.K. - E.U. - Worldwide Expedition 20 The official embroidered patch for the International Space Station Expedition 20 crew is now available from our stores.Current Shuttle Mission Patch The official embroidered patch for shuttle Atlantis' flight to deliver critical spare equipment to the space station.![]() Ares Patch The Ares Project will develop two new rockets to launch astronauts back to the Moon under NASA's Vision for Exploration. The Ares 1 will employ a single space shuttle solid rocket booster to loft the Orion crew capsule. The gigantic Ares 5 will haul the equipment and cargo needed for such lunar voyages. This is the Ares emblem.One Giant Leap
Hosted by Corbin Bernsen, this award winning documentary marks the 50th anniversary of the U.S. space agency and features exclusive interviews with veteran astronauts.Expedition 21 The official embroidered patch for the International Space Station Expedition 21 crew is now available from our stores.
An insider's view of how Apollo flight controllers operated and just what they faced when events were crucial.U.S. Apollo 11 special patch Special collectors' patch marking the 35th anniversary of the historic Apollo 11 moon landing is now available.U.S. - U.K. - E.U. - Worldwide Inside Apollo mission control
An insider's view of how Apollo flight controllers operated and just what they faced when events were crucial.U.S. The ultimate Apollo 11 DVD This exceptional chronicle of the historic Apollo 11 lunar landing mission features new digital transfers of film and television coverage unmatched by any other.U.S. - U.K. - E.U. - Worldwide Next ISS crew
Own a little piece of history with this official patch for the International Space Station's Expedition 11 crew. We'll ship yours today!U.S. Apollo 12 tribute DVD set ![]() New! Featuring the jovial crew of Pete Conrad, Dick Gordon and Alan Bean, the Apollo 12 mission was struck by lightning shortly after liftoff but proceeded on the second successful exploration voyage to the lunar surface. This three-disc DVD brings the mission to life with extraordinary detail. U.S. - U.K. - E.U. - Worldwide Fallen Heroes special patch This special 12-inch embroidered patch commemorates the U.S. astronauts who made the ultimate sacrifice, honoring the crews of Apollo 1, Challenger and Columbia.U.S. - U.K. - E.U. - Worldwide Women in Space Women of Space: Cool Careers on the Final Frontier is for girls, young women, and anyone else interested in learning about exciting careers in space exploration. Includes CD-ROM.U.S. - U.K. - E.U. - Worldwide Mars rover poster This new poster features some of the best pictures from NASA's amazing Mars Exploration Rovers Spirit and Opportunity.U.S. Get e-mail updates Sign up for our NewsAlert service and have the latest news in astronomy and space e-mailed direct to your desktop (privacy note: your e-mail address will not be used for any other purpose). |
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