- The long-delayed launch of a UC Berkeley/NASA satellite
to study violent explosions on the sun is now set for next
Tuesday, Feb. 5, from the belly of an Orbital Sciences Corp.
plane over the Atlantic Ocean.
Energy Solar Spectroscopic Imager, or HESSI, designed, built
and operated by an international consortium led by scientists
at the University of California, Berkeley, will embark on
a two- to three-year mission to look at high-energy X-ray
and gamma ray emissions from solar flares. Though various
satellites have made X-ray and gamma ray observations of flares,
which are enormous explosions in the solar atmosphere, HESSI
will be the first to snap pictures in gamma rays and the highest
originally scheduled for launch in July 2000, but was postponed
after the satellite suffered damage during vibration testing.
Since then, flight delays due to launch vehicle failures have
affected the launch date. However, officials have since cleared
the way for next Tuesday's scheduled launch.
P. Lin, professor of physics in the College of Letters & Science
at UC Berkeley and principal investigator for the mission,
is optimistic that HESSI will achieve its original scientific
aiming for the peak of solar activity in mid-2000, so we have
been lucky that, with the slip of our launch date by a year
and a half, solar activity has continued to stay high," Lin
said. "The sun had another peak of activity at the end of
2001. We still think we will image around a thousand solar
flares, though whatever we see will be new and interesting."
whose total mission cost is $85 million, is the sixth Small
Explorer (SMEX) spacecraft scheduled for launch under NASA's
EVENT - MONDAY, FEB. 4
2-3 p.m. EST
Kennedy Space Center, a combination mission and science briefing. Participants
will discuss the overall mission, the launch vehicle, spacecraft health,
and timeline between separation from the Pegasus rocket through start
of science operations. Scientists will discuss details of the science
payload and science objectives for the mission. NASA will provide live
broadcast via NASA-TV. The news conference also will be streamed through
the web from the KSC Web site at http://www.ksc.nasa.gov/.
Robert P. Lin, UC Berkeley principal investigator for HESSI
Brian Dennis, HESSI mission scientist at Goddard Bill Wagner,
NASA's Sun-Earth Connection program manager
West Coast reporters may view the Florida news briefing from
the conference room at the University of California, Berkeley's
Space Sciences Laboratory beginning at 10:30 a.m. PST. Several
HESSI scientists will be at the lab. The lab is at the top
of Centennial Drive near its intersection with Grizzly Peak
Boulevard. Please check in at the front office for parking
DAY EVENTS - TUESDAY, FEB. 5
NASA-TV coverage and commentary of the HESSI launch, including L-1011
take-off from Cape Canaveral, Fla., and drop of the Pegasus rocket.
The launch as seen from a chase plane will be on NASA-TV or on the Web
Coverage begins at about 2:00 p.m. EST. L-1011 take off is
at 2:30 p.m., with Pegasus drop scheduled for 3:26 p.m. EST.
Viewing of the launch at UC Berkeley's Space Sciences Laboratory
via live satellite feed from NASA-TV. HESSI scientists in
the Mission & Science Operations Center (MSOC) will provide
regular updates. The main update will be given after the satellite's
first pass over Berkeley, at about 2 p.m. PST. By then, HESSI
scientists should have information about the health of the
Robert P. Lin, HESSI principal investigator, UC Berkeley professor
of physics, director of UC Berkeley's Space Sciences Laboratory
Manfred Bester, lead scientist in HESSI Mission Operations
Center, UC Berkeley David Smith, spectrometer development
scientist, UC Berkeley
10:30 a.m. - 3 p.m. PST
room, first floor of Silver Laboratory Addition, UC Berkeley.