Launch of NASA's Gamma-ray Large Area Space Telescope, or GLAST, is targeted for Tuesday, June 3, from Pad 17-B at Cape Canaveral Air Force Station, Fla. The launch window extends from 11:45 a.m. to 1:40 p.m. EDT and remains unchanged through AugUST 7. The June 3 launch date is dependent on space shuttle Discovery's May 31 liftoff, and will move if the shuttle launch is delayed.

NASA's new gamma-ray observatory will open a wide window on the universe through the study of Gamma rays, the highest-energy form of light. GLAST data will enable scientists to answer persistent questions across a broad range of topics, including supermassive black-hole systems, pulsars, the origin of cosmic rays, and searches for signals of new physics.

NASA will hold a pre-launch news conference at NASA's Kennedy Space Center news center at 1 p.m. on Sunday, June 1. The briefing will be carried live on NASA Television.

A prelaunch webcast will take place on Monday, June 2 at noon on NASA Direct, Kennedy's Internet broadcasting network. GLAST's launch director will explain how the countdown will unfold on launch day, discuss how the spacecraft and Delta II launch vehicle were prepared for liftoff, and viewers will hear GLAST's project scientist explain the mission's goals.

On Sunday, June 1, NASA TV coverage of the GLAST pre-launch news conference at Kennedy will begin at 1 p.m. Two-way question and answer capability will be available from participating NASA locations. On Tuesday, June 3, NASA TV coverage of the launch will begin at 9:30 a.m. and conclude after spacecraft separation from the Delta II rocket, which occurs 75 minutes after launch. Coverage will be carried on the NASA TV Media Channel (Channel 103).

The broadcast network HDNet also will carry the launch in high-definition television format from 11:30 a.m. until noon. For complete NASA TV downlink information, schedules and links to streaming video, visit: