Boeing

The Sea Launch vessels arrived at the equatorial launch site this afternoon and immediately began the L-72 hour countdown to launch XM-1, the "Roll" satellite, on Tuesday, May 8.

The 45-minute launch window will open at 3:10 p.m. (PDT) on May 8 for liftoff of the second of two digital audio radio satellites, called "Rock" and "Roll." Boeing Satellite Systems, the world's leading provider of commercial communications satellites, built the powerful satellites for XM Satellite Radio (Nasdaq: XMSR) of Washington, D.C. The Boeing 702 models will each generate 18 kilowatts of total power at the beginning of life in orbit.

The Odyssey Launch Platform is ballasting to its launch depth - about 65 feet - in preparation for launch operations. This depth provides stability for the floating platform's marine and launch environments. The Sea Launch Commander, known as the Assembly and Command Ship, is currently alongside the Odyssey and will be connected by a "link bridge" during launch preparations. At the time of launch, the Ship will move to a launch position of 3.5 miles from the Platform, with crews from both vessels aboard for operations safety. The launch site is located on the Equator in open waters of the South Pacific, at 154 West Longitude.

The Sea Launch Zenit-3SL launch vehicle will loft the 10,289 lb (4,672 kg) payload to Geosynchronous Transfer Orbit, with the spacecraft separating from the upper stage at an altitude of about 1,600 miles above the Indian Ocean. Once in space, "Roll" will be positioned in Geostationary Orbit, 35,786 km (22,236 miles) above the Earth, at 85 degrees West Longitude. Designed for a 15-year lifespan, "Rock" and "Roll" will transmit up to 100 channels of digital radio across the United States, including music, news, sports, talk, comedy and children's programming.

Sea Launch will provide a live satellite broadcast and simultaneous webcast of the launch on May 8, beginning at 2:50 p.m. PDT. The program will include a live video transmission from the Equator and commentary from a studio at Sea Launch Home Port in Long Beach. Viewers in the United States may downlink the launch in NTSC from: GE 3C Transponder 12; C-Band Analog; Orbital Position 87 degrees (w); Downlink Frequency 3940 MHz (v).

Members of the print and broadcast media seeking information and high-resolution images are directed to a media-specific Sea Launch website.