Editorial questioning the House subcommittee decision on the space station, noting that this is the same committee that requested the latest redesign. "The panel has not plausibly explained, let alone justified, its about-face."
Soyuz TM-12, carrying replacement Mir crew Artsebarsky and Kirkalov plus Juno cosmonaut Helen Mace, docks with Mir May 20 after the damaged guidance antenna on Mir forces a manually-controlled approach.
House defense bill funds SDI at $2.7G but Brilliant Pebbles at 0.
White House and NASA gear up to fight the House move to kill Fred, as the international partners object loudly. ESA Director General Jean-Marie Luton says treating such a major project this way "does great damage to credibility in US international cooperative commitments". Japanese response, now in preparation, will be similar; Lenoir says the Japanese have told Truly that they will pursue their own space station if the US abandons the project.
Astro 2 comes back from the dead: the Astro ultraviolet telescope package will fly again in 1993.
Shuttle management investigating why it took so long to find out that a defective temperature probe removed from Columbia was in fact a serious hazard. The sensor was a minor contributor to Columbia's hydrogen leaks last fall, but on analysis a much graver problem turned up. The sensor was badly cracked and part might have broken off and gotten into the fuel flow... just upstream of the turbopumps. There are nine of these sensors in the orbiter plumbing, and the six monitoring temperatures just above the engines have no filters between them and the pumps. Word of this reached NASA well into Columbia's countdown, which was scrubbed pending checks of all the sensors, underway now. The sensor may have flown with the crack several times. Discovery's sensors, more accessible since it isn't on the pad, include two cracked and two others that are being X-rayed. The underlying problem seems to be a minor design change made after the sensors malfunctioned during ground tests of the SSMEs ten years ago. Sensor spares have been X-rayed, and nine unquestionably good ones will be installed in Columbia to avoid further launch delay. In the long run, NASA is considering deleting some of the sensors, since they are basically leftovers from early development work.
More detail on Brilliant Eyes, SDI's proposed 50-satellite constellation of missile warning and tracking satellites. Each will weigh about 1000lbs and will carry a pair of infrared telescopes plus a lidar system to let a single satellite do a full trajectory determination of a missile. There is thought to be reasonable hope for this program even if Brilliant Pebbles goes down in flames, although a name change might be a good idea.
Preliminary results from the investigation of the Titan 4 upgraded-SRB explosion: a combination of an unexpected pattern of gas flow and deformation of the fuel restricted gas flow enough to cause a rapid pressure buildup. Relatively minor changes to fuel shape should suffice as a fix. The second test motor will be modified accordingly before firing next spring. Rebuilding the test stand is actually going to be the biggest delay.
Lightweight protocols? TCP/IP *is* | Henry Spencer @ U of Toronto Zoology lightweight already; just look at OSI. | henry@zoo.toronto.edu utzoo!henry