Hello All!   
      
   Dawn Spacecraft Snaps Close-up Image of Asteroid Vesta *   
      
   July 18, 2011: NASA's Dawn spacecraft has returned the first close-up image   
   after beginning its orbit around the giant asteroid Vesta. On Friday, July 15,   
   Dawn became the first probe to enter orbit around an object in the main   
   asteroid belt between Mars and Jupiter.    
      
   The image taken for navigation purposes shows Vesta in greater detail than   
   ever before. When Vesta captured Dawn into its orbit, there were approximately   
   9,900 miles (16,000 kilometers) between the spacecraft and asteroid. Engineers   
   estimate the orbit capture took place at 10 p.m. PDT Friday, July 15 (1 a.m.   
   EDT Saturday, July 16).    
   [...]   
   This is the first image obtained by NASA's Dawn spacecraft after successfully   
   entering orbit around Vesta. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA   
   [more]    
      
   Vesta is 330 miles (530 kilometers) in diameter and the second most massive   
   object in the asteroid belt. Ground- and space-based telescopes have obtained   
   images of Vesta for about two centuries, but they have not been able to see   
   much detail on its surface. "We are beginning the study of arguably the oldest   
   extant primordial surface in the solar system," said Dawn principal   
   investigator Christopher Russell from the University of California, Los   
   Angeles. "This region of space has been ignored for far too long. So far, the   
   images received to date reveal a complex surface that seems to have preserved   
   some of the earliest events in Vesta's history, as well as logging the   
   onslaught that Vesta has suffered in the intervening eons."    
      
   Vesta is thought to be the source of a large number of meteorites that fall to   
   Earth. Vesta and its new NASA neighbor, Dawn, are currently approximately 117   
   million miles (188 million kilometers) away from Earth. The Dawn team will   
   begin gathering science data in August. Observations will provide   
   unprecedented data to help scientists understand the earliest chapter of our   
   solar system. The data also will help pave the way for future human space   
   missions.    
      
   After traveling nearly four years and 1.7 billion miles (2.8 billion   
   kilometers), Dawn also accomplished the largest propulsive acceleration of any   
   spacecraft, with a change in velocity of more than 4.2 miles per second (6.7   
   kilometers per second), due to its ion engines. The engines expel ions to   
   create thrust and provide higher spacecraft speeds than any other technology   
   currently available. "Dawn slipped gently into orbit with the same grace it   
   has displayed during its years of ion thrusting through interplanetary space,"   
   said Marc Rayman, Dawn chief engineer and mission manager at NASA's Jet   
   Propulsion Laboratory in Pasadena, Calif. "It is fantastically exciting that   
   we will begin providing humankind its first detailed views of one of the last   
   unexplored worlds in the inner solar system."    
      
   Although orbit capture is complete, the approach phase will continue for about   
   three weeks. During approach, the Dawn team will continue a search for   
   possible moons around the asteroid; obtain more images for navigation; observe   
   Vesta's physical properties; and obtain calibration data.    
      
   In addition, navigators will measure the strength of Vesta's gravitational tug   
   on the spacecraft to compute the asteroid's mass with much greater accuracy   
   than has been previously available. That will allow them to refine the time of   
   orbit insertion.    
      
   Dawn will spend one year orbiting Vesta, then travel to a second destination,   
   the dwarf planet Ceres, arriving in February 2015.    
      
   For more information about Dawn, visit: http://www.nasa.gov/dawn and   
   http://dawn.jpl.nasa.gov . You can also follow Dawn on Twitter at:   
   http://www.twitter.com/NASA_Dawn .    
      
   * http://science.nasa.gov/science-news/science-at-nasa/2011/18jul_dawn4/    
      
   Editor: Dr. Tony Phillips | Credit: Science@NASA   
      
   More Information    
   Dawn Journal -- penned by Dawn's chief engineer Marc Rayman    
      
   Does Asteroid Vesta Have a Moon?  -- from Science@NASA    
      
   Vesta--Is it Really an Asteroid?  -- from Science@NASA    
      
   Credits: The mission to Vesta and Ceres is managed by JPL for the agency's   
   Science Mission Directorate in Washington. Dawn is a project of the   
   directorate's Discovery Program, which is managed by NASA's Marshall Space   
   Flight Center in Huntsville, Ala.    
      
   UCLA is responsible for Dawn mission science. Orbital Sciences Corp. of   
   Dulles, Va., designed and built the spacecraft. The German Aerospace Center,   
   the Max Planck Institute for Solar System Research, the Italian Space Agency   
   and the Italian National Astrophysical Institute are part of the mission's   
   team.    
       
      
   Regards,   
      
   Roger    
   --- timEd/386 1.10.y2k+   
    * Origin: NCS BBS - Houma, LA - (1:3828/7)