June 20, 2011 Dwayne Brown Headquarters, Washington 202-358-1726 dwayne.c.brown@xxxxxxxx Jia-Rui Cook/Priscilla Vega Jet Propulsion Laboratory, Pasadena, Calif. 818-354-0850/1357 jccook@xxxxxxxxxxxx/priscilla.r.vega@xxxxxxxxxxxx MEDIA ADVISORY: M11-126 NASA HOSTS BRIEFING TO PREVIEW SPACECRAFT VISIT OF LARGE ASTEROID WASHINGTON -- NASA will host a news briefing at 2 p.m. EDT on Thursday, June 23, to discuss the Dawn spacecraft's year-long visit to the large asteroid Vesta. The mission expects to go into orbit around Vesta on July 16 and begin gathering science data in early August. The briefing will be held in the NASA Headquarters auditorium located at 300 E St. SW, in Washington. NASA Television and the agency's website will broadcast the event. Dawn's visit to Vesta will be the first prolonged encounter to a main belt asteroid and the first trip to a protoplanet, or large body that almost became a planet. Observations will help understand the earliest chapter of our solar system's history. The briefing panelists are: -- W. James Adams, deputy director, Planetary Science Directorate, NASA Headquarters -- Robert Mase, Dawn project manager, Jet Propulsion Laboratory (JPL), Pasadena, Calif. -- Christopher Russell, Dawn principal investigator, UCLA -- Carol Raymond, Dawn deputy principal investigator, JPL Reporters may attend the event, ask questions from participating NASA locations or join by phone. To obtain dial-in information, journalists must e-mail Dwayne Brown at dwayne.c.brown@xxxxxxxx with their name, media affiliation and work telephone number by 11 a.m. on June 23. For more information about Dawn, visit: http://www.nasa.gov/dawn For NASA TV streaming video, downlink and schedule information, visit: http://www.nasa.gov/ntv The briefing also will be carried live on Ustream, with a live chat box available, at http://www.ustream.tv/nasajpl2 -end- To subscribe to the list, send a message to: hqnews-subscribe@xxxxxxxxxxxxxxxxxxxxxx To remove your address from the list, send a message to: hqnews-unsubscribe@xxxxxxxxxxxxxxxxxxxxxx