The launch of an advanced version of the KH-11 imaging reconnaissance satellite on a Titan 4 from Vandenberg AFB, Calif., Dec. 20, completes a new three-spacecraft constellation that uses an uprated model of the optical spacecraft operated by the National Reconnaissance Office (NRO).

The Russian Mars 96 mission with an orbiter, four landers and participants from more than 20 countries is scheduled to be en route to Mars this week after a tortuous eight-year development that spanned the collapse of the Soviet Union.

The launch of MGS is the first step toward establishing an international robotic infrastructure at Mars.

WorldSpace's $750-million investment in a digital radio broadcast network is expected to make its first profits 2-3 years after launching the startup company's three spacecraft in 1998-99.

ASTRONOMERS FROM Johns Hopkins University and the Space Telescope Science Institute have discovered what they believe is a thin oxygen atmosphere on Ganymede, the largest of Jupiter's 16 moons. The team studied ultraviolet observations of Ganymede made with the Hubble Space Telescope's Goddard High Resolution Spectrograph. It showed that the moon probably has an atmosphere with pressure comparable to Earth's atmosphere at several hundred km. altitude--roughly the level of space shuttle orbits.

NASA has formed a five-man incident investigation board to study the loss of the NASA/McDonnell Douglas DC-XA experimental rocket on July 31, when one retracted landing gear leg caused it to fall over and burn after a successful touchdown (AW&ST Aug. 5, p. 22).

NASA is carefully removing human space flight control from the proven realm of custom software and massive mainframe computers and bringing it at long last to the flexible world of networked workstations.

The Galileo spacecraft is set to release its Jupiter atmospheric probe on Thursday.