SWAS was successfully launched December 5, 1998 at about 16:57 PST. It was the third launch attempt.
December 1, 1998 - 14:40 EST
SWAS remains on schedule for a 2 December launch despite stormy weather that prevented the roll-out of the Pegasus-XL vehicle to the Hot Pad area yesterday. The launch window extends from 16:40 to 18:04 Pacific Standard Time (PST) with drop of the Pegasus-XL rocket from the Orbital Sciences carrier aircraft targeted for 16:45 PST. Clearing weather coupled with forecasts of improving weather over the next few days led to the decision to roll the vehicle out of its hangar today (1 December). This occurred at 5 AM local time. The Pegasus-XL is now at the Hot Pad. Activities for today include mechanical and electrical mating to its carrier aircraft, a specially modified L-1011. A launch pad functional test will then follow. Both a Launch Readiness Review and a Flight Readiness Review will also take place this afternoon.
As of 11AM PST (1 December), the Pegasus rocket has been successfully mated to the L-1011.
Kennedy Space Center
Nov. 25, 1998
The 625-pound SWAS spacecraft's mission is designed to help scientists gain a greater understanding of star formation by determining the composition of interstellar clouds, and establishing the means by which these clouds cool as they collapse to form stars and planets. During the two-year mission, the spacecraft will observe hundreds of regions of ongoing star formation within our galaxy. SWAS will be placed into a 370-mile polar orbit circling the Earth every 97 minutes. SWAS is one of NASA's Small Explorers (SMEX) designed and built by Goddard Space Flight Center, Greenbelt, Md. The launch program and countdown management for Pegasus/SWAS is directed by the Kennedy Space Center.
NASA Headquarters, Washington, DC
Goddard Space Flight Center, Greenbelt, MD
November 25, 1998
The overall goal of the two-year mission is to gain a greater understanding of star formation by determining the composition of interstellar clouds, and establishing the means by which these clouds cool as they collapse to form stars and planets.
"During its mission, SWAS will observe hundreds of regions of ongoing star formation within our galaxy. The answers SWAS will provide are important not only to the understanding of the formation of future stellar systems, but also to the understanding of the processes that led to the formation of the Sun, the Earth, and the other planets and moons in our own solar system," said Dr. Gary Melnick, Harvard-Smithsonian Center for Astrophysics, principal investigator for the SWAS mission.
SWAS will be launched from Vandenberg Air Force Base, CA, via a Pegasus-XL launch vehicle, built by Orbital Sciences Corporation. The launch vehicle is a three-stage, solid- propellant booster system carried aloft by an L-1011 jet aircraft. The system will be released when the aircraft reaches an altitude of about 40,000 feet (12,200 meters) and has airspeed of Mach 0.8. The SWAS mission is designed for a two-year duration.
SWAS is one of NASA's Small Explorers (SMEX) satellites, which are both small and economical. The SWAS spacecraft weighs only 625 pounds. The satellite was designed and built by NASA's Goddard Space Flight Center, Greenbelt, MD.
The SWAS observatory will be inserted into an orbit with an altitude of 370 miles above the Earth, and will orbit the Earth every 97 minutes. SWAS will typically observe three to five astronomical objects per orbit. The observed data will be stored in the spacecraft memory and sent to a ground station. Within 24 hours of receipt at the ground station, these data are received at the Smithsonian Astrophysical Observatory's Science Operation Center in Cambridge, MA. There, the science content of the data is analyzed and new astronomical targets are selected for observation.
Further information about SWAS can be found on the Internet at: