 | Iridium
Credit - Lockheed-Martin
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Class: Communications. Destination: Medium Earth Orbit. Nation: USA. Agency: Iridium Corp. (Motorola commercial venture). Manufacturer: Motorola, Lockheed. The LM 700 had its first use in the Iridium system, a commercial communications network comprised of a minimum of 66 LEO spacecraft. The system used L-Band to provide global communications services through portable handsets. A total of 125 spacecraft were to be built by Lockheed for more than $700M. However Iridium went bankrupt in 1999 after 90 had been launched. However the constellation remained in use for specialized users and a launch in 2002 replenished the constellation. The spacecraft itself was three-axis stabilized with a hydrazine propulsion system. Power was supplied by two solar panels with 1-axis articulation. The system employed L-Band using FDMA/ TDMA to provide voice at 4.8 kbps and data at 2400 bps with 16 dB margin. Each satellite had 48 spot beams for Earth coverage and used Ka-Band for crosslinks and ground commanding. Design Life: 8 years. Typical orbit: MEO, 780 km circular, 75 deg inclination, 6 planes. Length: 4.00 m (13.10 ft). Maximum Diameter: 1.30 m (4.20 ft). Mass: 689 kg (1,518 lb). Associated Launch Vehicle: Atlas IIIB, CZ-2C/SD, Delta 7000, Proton 8K82K / 17S40, Rokot.
LM 700 Chronology
- 1998 April 7 - Iridium 68 - Program: Iridium. Launch Site: Baikonur. Launch Vehicle: Proton 8K82K / 17S40. Mass: 689 kg (1,518 lb). Perigee: 776 km (482 mi). Apogee: 779 km (484 mi). Inclination: 86.40 deg. Period: 100.40 min.
The Proton launch vehicle placed the Iridium cluster and the Block DM2 stage into low parking orbit. The DM2 fired twice to enter the deployment orbit and dispensed the seven satellites, which used their own propulsion units to reach operational altitude. The DM2 stage then fired again to deorbit itself, to avoid creating space debris. SV068 placed in Plane 1. Ascending node 167.8 degrees.
- 1999 June 11 - Iridium 21A - Program: Iridium. Launch Site: Taiyuan. Launch Vehicle: CZ-2C/SD. Perigee: 708 km (439 mi). Apogee: 711 km (441 mi). Inclination: 86.50 deg. Period: 99.00 min.
- 1999 June 11 - Iridium 14A - Program: Iridium. Launch Site: Taiyuan. Launch Vehicle: CZ-2C/SD. Perigee: 708 km (439 mi). Apogee: 711 km (441 mi). Inclination: 86.50 deg. Period: 99.00 min.
- 2002 February 11 - Iridium - Program: Iridium. Launch Site: Vandenberg. Launch Vehicle: Delta 7000. Mass: 690 kg (1,520 lb). Perigee: 665 km (413 mi). Apogee: 679 km (421 mi). Inclination: 86.60 deg. Period: 98.20 min.
- 2002 February 11 - Iridium - Program: Iridium. Launch Site: Vandenberg. Launch Vehicle: Delta 7000. Mass: 690 kg (1,520 lb). Perigee: 667 km (414 mi). Apogee: 677 km (420 mi). Inclination: 86.60 deg. Period: 98.20 min.
- 2002 February 11 - Iridium - Program: Iridium. Launch Site: Vandenberg. Launch Vehicle: Delta 7000. Mass: 690 kg (1,520 lb). Perigee: 665 km (413 mi). Apogee: 679 km (421 mi). Inclination: 86.60 deg. Period: 98.20 min.
Mobile Telephony satellite. Return to flight after GEM solid booster failure on GBI launch. Launch delayed from February 8, 9 and 10. Five Motorola Iridium satellites were launched for Iridium Satellite LLC, the new company that bought out the bankrupt Iridium LLC. This was the first system replenishment launch since the bankruptcy.
- 2002 February 11 - Iridium - Program: Iridium. Launch Site: Vandenberg. Launch Vehicle: Delta 7000. Mass: 690 kg (1,520 lb). Perigee: 665 km (413 mi). Apogee: 679 km (421 mi). Inclination: 86.60 deg. Period: 98.20 min.
- 2002 February 11 - Iridium - Program: Iridium. Launch Site: Vandenberg. Launch Vehicle: Delta 7000. Mass: 690 kg (1,520 lb). Perigee: 660 km (410 mi). Apogee: 684 km (425 mi). Inclination: 86.60 deg. Period: 98.20 min.
- 2002 February 21 - Echostar 7 - Program: Echostar. Launch Site: Cape Canaveral. Launch Vehicle: Atlas IIIB. Mass: 690 kg (1,520 lb). Perigee: 35,779 km (22,231 mi). Apogee: 35,794 km (22,241 mi). Inclination: 0.10 deg. Period: 1,436.10 min.
Direct Broasdcasting satellite. The first launch of the Atlas 3B, with the Common Centaur stretched two-engine upper stage. Launch delayed from December 19, 2001 and January 22. The Echostar 7 communications satellite was placed into geostationary transfer orbit. The first burn of the Centaur put the stack into a 185 x 193 km x 28.1 deg parking orbit. At 1305 UTC the Centaur burned again to achieve the final 245 x 57060 km x 22.6 deg transfer orbit and separated from Echostar. As of 2007 Mar 11 located at 118.92W drifting at 0.006W degrees per day.
- 2002 June 20 - Iridium SV98 - Program: Iridium. Launch Site: Plesetsk. Launch Vehicle: Rokot. Mass: 690 kg (1,520 lb). Perigee: 658 km (408 mi). Apogee: 666 km (413 mi). Inclination: 86.60 deg. Period: 98.00 min.
Bibliography and Further Reading
- McDowell, Jonathan, Jonathan's Space Report (Internet Newsletter), Harvard University, Weekly, 1989 to Present. Essential internet newsletter recording worldwide weekly space events. Accessed at: http://www.planet4589.org/jsr.html.
- Vladimirov, A, Novosti kosmonavtiki, "Tablitsa zapuskov RN 'Proton' i 'Proton K'", 1998, Issue 10, page 25.
- NASA GSFC Orbital Parameters, .
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