Allen Thomson has pointed out that LES-8 (76-23A, 8746) and LES-9 (76-23B, 8747) carry RTGs. This is confirmed by Jean-Philippe Donnio's Satellite Encyclopedia: "LES 8 & 9 were placed in geostationary orbit with 90 deg between each other. Equipped with a radio isotropic 238 plutonium generator, they could communicate without the help of a ground station". I looked up LES in Jane's Spaceflight Directory 1986 and found: "Tacsat Tactical communications satellites (Tacsat) need much greater onboard power than conventional comsats so that they can work with small ground terminals carried by ships, tanks, jeeps and aircraft. LES 5 (Lincoln Experiment Satellite), launched 1 Jul 1967 ... was America's first. 2 days after it had been manoeuvred into a 33,360 km, near-synchronous orbit, the 1st satellite communications between US aircraft, a US Navy submarine and surface vessel, and Army ground units had been carried out. The follow-on Tacsat 1 ... was designed to communicate with tiny land based receivers using aerials 0.3m in dia." So my list of US radioactive payloads/debris has changed to: US-SNAP (Systems for Nuclear Auxiliary Power): 116 61-015A TRANSIT 4A US 103.6 66.8 984 872 2.4 202 61-031A TRANSIT 4B US 105.7 32.4 1101 950 5.5 1314 65-027A OPS 4682 (SNAPSHOT) US 111.5 90.2 1317 1273 10.2 3890 69-037A NIMBUS 3 US 107.3 100.1 1131 1072 5.1 8746 76-023A LES 8 US 1436.2 15.6 35832 35746 1.9 8747 76-023B LES 9 US 1436.1 15.6 35882 35690 4.0 US-SNAP? 2866 67-066E LES 5 US 1316.0 12.3 33623 33183 3.0 3431 68-081D LES 6 US 1435.7 13.6 35832 35726 2.5 3691 69-013A TACSAT (OPS 0757) US 1435.5 14.5 35801 35748 Rainer Kracht 1996 Jan 24 0412188960-0001@t-online.de R.Kracht@t-online.de