Jun 13 2011
From The Space Library
RELEASE: 11-182 NASA SPACECRAFT CAPTURES VIDEO OF ASTEROID APPROACH
WASHINGTON -- Scientists working with NASA's Dawn spacecraft have created a new video showing the giant asteroid Vesta as the spacecraft approaches this unexplored world in the main asteroid belt. The video loops 20 images obtained for navigation purposes on June 1. The images show a dark feature near Vesta's equator moving from left to right across the field of view as Vesta rotates. Images also show Vesta's jagged, irregular shape, hinting at the enormous crater known to exist at Vesta's south pole. The images were obtained by a framing camera during a 30-minute period and show about 30 degrees of a rotation. The pixel size in these images is approaching the resolution of the best Hubble Space Telescope images of Vesta. "Like strangers in a strange land, we're looking for familiar landmarks," said Jian-Yang Li, a Dawn participating scientist from the University of Maryland, College Park. "The shadowy spot is one of those - it appears to match a feature, known as 'Feature B,' from images of Vesta taken by NASA's Hubble Space Telescope." Before orbiting Vesta on July 16, Dawn will gently slow down to about 75 mph (120 kph). NASA is expecting to release more images on a weekly basis, with more frequent images available once the spacecraft begins collecting science at Vesta. "Vesta is coming more and more into focus," said Andreas Nathues, framing camera lead investigator, based at the Max Planck Institute for Solar System Research, Katlenburg-Lindau, Germany. "Dawn's framing camera is working exactly as anticipated." The mission is managed by NASA's Jet Propulsion Laboratory in Pasadena, Calif., for the agency's Science Mission Directorate in Washington. Dawn is a project of the directorate's Discovery Program, managed by NASA's Marshall Space Flight Center in Huntsville, Ala. UCLA is responsible for overall Dawn mission science. Orbital Sciences Corp. of Dulles, Va., designed and built the Dawn spacecraft. The framing cameras were developed and built under the leadership of the Max Planck Institute for Solar System Research in Katlenburg-Lindau, Germay. The German Aerospace Center (DLR) Institute of Planetary Research in Berlin made significant contributions in coordination with the Institute of Computer and Communication Network Engineering in Braunschweig. The framing camera project is funded by the Max Planck Society, DLR and NASA. The video from Dawn also will air Monday afternoon on NASA Television's Video File.
RELEASE: 11-184 UPPER STAGE ENGINE READY FOR TESTING AT NASA'S STENNIS SPACE CENTER BAY ST. LOUIS, Miss. --
NASA's new J-2X rocket engine, which could power the upper stage of the nation's future heavy-lift launch vehicle, is ready for its first round of testing. The fully assembled engine was installed Saturday in the A-2 Test Stand at the agency's Stennis Space Center in Mississippi. Beginning in mid-June, the engine will undergo a series of 10 test firings that will last several months. "An upper stage engine is essential to making space exploration outside low-Earth orbit a reality," said Mike Kynard, manager of the J-2X upper stage engine project at NASA's Marshall Space Flight Center in Huntsville, Ala. "The J-2X goes beyond the limits of its historic predecessor and achieves higher thrust, performance, and reliability than the J2. We are thrilled to have the engine in the test stand to validate our assumptions about engine performance and reliability." The test stand, which supported the space shuttle main engine project, has been modified to accommodate the J-2X engine's different shape. In addition to the structural, electrical and plumbing modifications, a new engine start system was installed and control systems were upgraded on the stand. The liquid oxygen and liquid hydrogen transfer lines that dated back to the 1960s were replaced. Fueled by liquid oxygen and liquid hydrogen, the J-2X engine will generate 294,000 pounds of thrust in its primary operating mode to propel a spacecraft into low-Earth orbit. By changing the mixture ratio of liquid oxygen to liquid hydrogen, the J-2X can operate in a secondary mode of 242,000 pounds of thrust required to power a spacecraft from low-Earth orbit to the moon, an asteroid or other celestial destination. The J-2X can start and restart in space to support a variety of mission requirements. "We are excited to have a new engine in the A-2 Test Stand," said Gary Benton, manager of the J-2X engine testing project at Stennis. "Installation of the J-2X engine marks the beginning of the third major rocket engine test project on this historic stand." The A-2 Test Stand originally was used to test Saturn V rocket stages for NASA's Apollo Program. In the mid-1970s, the stand was modified from Apollo Program parameters to allow testing of space shuttle main engines. Pratt & Whitney Rocketdyne of Canoga Park, Calif., designed and built the J-2X for NASA.
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