June 26, 2000

Payload: Sirius-1
Space Systems/Loral 1300 platform
High-powered digital audio radio service satellites (DARS)

Separated mass: Approx. 3800 kg (8,377 lbs)

Launch Vehicle: Proton/Block DM

Weight at liftoff: 780 metric tons (1,719,606 lbs), including payload

Launch Date: Saturday, July 1, 2000 (Baikonur Time)

Launch Window Open:

04:08:47 (Baikonur Time)
02:08:47 (Moscow Time)
6:08:47 p.m. (EDT/USA) June 30
22:08:47 (UTC) June 30

Launch Site: Baikonur Cosmodrome, Kazakhstan
Launch Complex 81, Pad 24

End User: Sirius Satellite Radio www.siriusradio.com, the pioneer in the emerging satellite radio industry plans to deliver by subscription 50 channels of commercial-free music and up to 50 channels of entertainment programming

Satellite Manufacturer: Space Systems/Loral, Palo Alto, CA, USA

Launch Vehicle Manufacturer: Khrunichev State Research and Production Space Center, Moscow — Proton first three stages; RSC Energia, outside of
Moscow — Block DM fourth stage

Launch Services Provider: International Launch Services (ILS) – an international launch services provider based in Reston, VA, USA, formed by Lockheed Martin Corp., Khrunichev and Energia

Satellite Use: One of three satellites for a digital satellite radio system that will broadcast unique music and entertainment programming to motorists throughout the continental U.S.

Satellite Status:
First satellite in the Sirius constellation
Orbital location: inclined elliptical orbit
Signals to be transmitted via the S-band
Optimized for a service life of 15 years or more

Mission Profile: The flight of the Proton launch vehicle’s first three stages will place the fourth stage and Sirius-1 into a nearly elliptical 170 km parking orbit. Two burns of the Block DM3 engine will inject the Sirius-1 spacecraft into a highly inclined elliptical orbit.

Spacecraft Separation: Approximately 2 hours, 25 minutes, 10 seconds after liftoff

ILS Mission Stats:
Second ILS mission on Proton this year
15th mission on Proton since formation of the Russian joint venture

Live Broadcast: Telstar 5, Transponder 4 Analog Ku. Test signals to begin at 5:30 p.m. EDT

More Information: General Proton information is available on the ILS web site at www.ilslaunch.com. Launch status updates are available on the ILS U.S. domestic Launch Hotline at 1-800-852-4980.

Contact Us!

For the latest news and information, or if you have a question, please email ILS at contactus@ilslaunch.com