Douglas Isbell 
Headquarters, Washington, DC              September 16, 1998
(Phone:  202/358-1547)

John Watson
Jet Propulsion Laboratory, Pasadena, CA
(Phone:  818/354-5011)

NOTE TO EDITORS:  N98-57

DEEP SPACE 1 PRELAUNCH TECHNOLOGY 
BRIEFING SCHEDULED FOR SEPT. 22 

     Representatives from the team making final preparations to 
launch NASA's Deep Space 1 mission will conduct a televised media 
briefing on the mission and its goals on Tuesday, Sept. 22, at 2 
p.m. EDT.  The briefing will originate from NASA Headquarters in 
Washington, DC, and will be carried live on NASA TV. 

     Deep Space 1 is now officially scheduled for liftoff at 
6:59:50 a.m. EST on Oct. 25, 1998, aboard a Boeing Delta 7326 
launch vehicle from Cape Canaveral Air Station, FL.  However, 
mission managers continue to work toward a possible Oct. 15 
launch.  The recent change in the official launch date to Oct. 25 
is due to the high demand for launch pad time at Cape Canaveral.  
Given that missions are allowed to make firm reservations for just 
two consecutive days, Deep Space 1 mission engineers chose to move 
their single two-day reservation from Oct. 15-16 to Oct. 25-26 to 
ensure that the spacecraft would be ready for launch before 
subsequent Delta launches.  NASA officials will decide by the end 
of September whether to request a change back to Oct. 15-16 if 
final spacecraft processing remains on schedule and if the launch 
support system can accommodate the change at that time. 

     Deep Space 1 is the first mission in NASA's New Millennium 
Program, designed to test and validate new technologies so that 
they can be used confidently on science missions of the 21st 
century.  Although Deep Space 1 will test two science instruments, 
this mission is one of the first-ever deep space NASA launches to 
have technology, rather than science, as its key focus.  Much of 
the key technology testing will be completed within eight weeks of 
launch.  However, Deep Space 1 plans to attempt an encounter with 
asteroid 1992 KD in July 1999 to demonstrate its technologies by 
observing a scientifically interesting body. 

     Presenters at the Sept. 22 press briefing are scheduled to 
include: 

Dr. Wesley T. Huntress Jr., NASA Associate Administrator for Space 
Science 
David Lehman, Deep Space 1 project manager, NASA's Jet Propulsion 
Laboratory (JPL), Pasadena, CA 
Dr. Marc Rayman, Deep Space 1 chief mission engineer and deputy 
mission manager at JPL 
Jack Stocky, manager, NASA Solar Electric Propulsion Technology 
Application Readiness (NSTAR) project at JPL 
Dr. Barbara Wilson, New Millennium Program technologist at JPL 

     NASA Television is located on GE-2, transponder 9C at 85 
degrees west longitude, vertical polarization, with a frequency of 
3880 MHz, and audio of 6.8 MHz.  There will be two-way question 
and answer capability for media at participating NASA centers.