STEX, 1998-055A, USA140 STEX, the Space Technology Experiments minisatellite was launched into a 665km orbit inclined at 85 degrees on the 3rd October 1998 on an ARPA Taurus launcher from VAFB. The [700,540kg] spacecraft was placed into a 697x716km orbit inclined at 85 degrees, and is expected to be boosted into a 800km circular orbit. The spacecraft was built by Lockheed Martin for the US National Reconnaissance Office (NRO) under a US$90m contract (1998), and carries 29 new technologies amongst which NRL experiments. Russian Xenon Hall-effect electric thrusters are carried delivering 40mN of thrust, a solid state data recorder, and NiH battery. ATEX, a 6km tether with TIPS heritage, but with two masses that will later be deployed as a separate sub-satellite. Frangibolts are used on the mission for shockless deployment of the spacecraft and tether. Experimental solar panel and batteries are also carried. A picture shows the spacecraft comprises a body shell and two tracking solar panels. A blowdown liquid propulsion system is carried, and the spacecraft is three axis controlled. On January 16th 1999, Atex was deployed, but failed. It was deployed together with its two tipmasses separated by 21m of tether, and is now tracked as a separate object (USA 141, 1998-055C) More... [ATEX at NRL]