In Recent Years Radioactive Materials from these Missions have crashed to the Earth or Burned in the Atmosphere
Mars 96 (Russia)
Reentry date: Nov. 16, 1996. Location: Chile or Bolivia; .44 lbs. of plutonium, thought to have burned and crashed near Northern Chile.
Cosmos 1402 (USSR)
Reentry date: Feb. 7, 1983. Location: South Atlantic; 68 lbs. of uranium-235. It is unknown if any debris reached the ground.
Cosmos 954 (USSR)
Reentry date: Jan. 24, 1978. Location: Northwest Territories, Canada; 68 lbs. of uranium 235. Scientists concluded that 75 percent of the radioactive material was vaporized and dispersed worldwide.
Rorsat Mission (USSR)
Reentry date: April, 1973. Location: Pacific Ocean, north of Japan. Radiation released from the reactor was detected.
Apollo 13 (US)
Reentry date: April 14, 1970. Location: South Figi. 5.5 lbs. of plutonium - 238 is believed to be intact on the ocean floor. Dr, Karl Grossman writes that Apollo 13's "SNAP-27" power pack carried 8.3 lbs. of plutonium and was jettisoned into the 3 1/2 mile deep Tonga Trench in the S. Pacific, off New Zealand.
Cosmos Lunar Missions (USSR)
Reentry date: 1969. Two missions failed. Radiation was detected as the crafts burned up in the atmosphere.
Nimbus B-1 (US)
Reentry date: May 18, 1968. The debris, including 4.2 lbs. of plutonium-238, landed in the Santa Barbara Channel off California. The fuel was recovered.
Transit 5BN-3 (US)
Reentry date: April 21, 1964. Location: Indian Ocean. 2.1 lbs. of plutonium-238 in a "SNAP-9A" vaporized in the atmosphere and spread worldwide, prompting the U.S. to redesign its RTGs. A group of European government agencies found SNAP-9A debris to be present on all continents and at all latitudes.
Chris Bryson, "How Safe are Nuclear-Powered Space Mission?" Christian Science Monitor, Dec. 17, 1996; David Chandler, "Hot Spot: Mars 96 Failure renews concern about plutonium-carrying spacecraft," The Boston Globe, Dec. 4, 1996; "U.S. is said to fumble space debris alert," Boston Globe, Dec. 9, 1996; Karl Grossman, "Risking the World: Nuclear Proliferation in Space," Covert Action Quarterly, Summer 1996.
Speaking of Reckless: The Cassini Space Probe
Other interesting Disarmament Links you may wish to follow.