May 1983:milestones

January 1983

22 The main section of Kosmos 1402 burns up in the atmosphere over the Indian Ocean. The nuclear core is expected to reenter early next month.

23 Japan's National Space Development Agency (NASDA) will shortly select at least three astronaut candidates to begin training before the end of this year; one of them will fly as a Shuttle payload specialist in about 1987.

24 It is reported that the seventh Shuttle mission might land at the Kennedy Space Center, but only if conditions are good and there are no problems with the STS-6 landing.

25 The STS-6 mission is delayed until mid-March at the earliest after a second test firing of Challenger's main engines shows there is a hydrogen leak in one or more of them. The delay now means that later flights will be affected but the Dept, of Defense is insisting that its military STS-10 payload flies this year. Spacelab (STS-9) could now be pushed into 1984 and some satellites might be switched to the Delta rocket.

26 The Infrared Astronomical Telescope (IRAS) is launched by a Delta rocket from the Vanderberg Air Force Base in California at 02:17 GMT into a polar orbit. After a two-week testing period it begins the first all-sky survey of infrared objects.

29 A 2 cm crack is found in Challenger's No. 1 engine (no. 2011) in a pipe routing hydrogen from cooling the engine back to the turbo pump. The engine will be replaced by flight spare no. 2016. Launch will be in mid-March at the earliest, later if a third engine firing is made.

31 The IRAS telescope's protective cover is ejected and the first infrared images of the sky are returned; more than 4,000 sources are detected on this first day. The rate of loss of liquid helium (used to cool the telescope to very low temperatures in order to observe IR objects) indicates a mission length of at least 250 days, more than enough time to scan the entire sky. The detectors prove to be 100 times more sensitive than previous missions.

February 1983

7 The section of Kosmos 1402 carrying a nuclear core reenters the atmosphere and disintegrates.

10 The replacement Shuttle main engine (no. 2016) is confirmed as having an oxygen leak. Two further replacement engines (nos. 2007 and 2017) will now be brought to the Cape. No. 2007 was recently removed from Orbiter Columbia and returned to the manufactureis for modifications.