henry@utzoo.uucp (Henry Spencer) (01/28/88)
Reagan-Gorbachev summit vaguely endorses international cooperation in
space. Gorbachev calls for joint manned Mars mission; no US response.
An attempt will be made to free the jammed solar array on TVSat 1 by
shaking the satellite with apogee-motor firings. It is in Clarke orbit
near its planned position, and the firings will contribute to moving it
there. This will minimize the waste of fuel, which otherwise could
shorten the satellite's useful life. The big question is how many of
the hold-down hooks failed to release; engineers are studying whether
a small thruster firing could make the solar array resonate at a
distinctive frequency that could be observed via the attitude gyros,
and whether the slight power loss caused by the shadows the hooks cast
on the outermost panel of the array could be distinctive at suitable
sun angles. Neither test will be tried until possible results are
thoroughly understood. If the array cannot be freed, then it will be
necessary to reduce the number of broadcast channels as the solar arrays
age, which will cause a political battle in Germany over who gets the
remaining ones. Another problem is that the satellite's main receiving
antenna cannot deploy fully unless the array is released, and nobody has
yet sorted out just where it is pointing as a result; no great amount of
time will be spent on this until the array issue is resolved.
Polar-platform meeting in Tokyo decides against French proposal to reduce
the size of the ESA polar platform. Original plan was a US platform in
1995, ESA's in 1997, another US one in 1997, and a Japanese one in 1998.
France proposed replacing the European platform with a Spot-sized satellite,
out of concern for the impact of reduced British contributions; Britain
was a major supporter of the European platform until its recent turnabout.
Nobody else liked the idea and the French backed down, but there may still
be trouble later.
NASA seeks ways to block expected Station budget cuts. Senator Garn says
there simply is no serious public support for it, in a time of tight money.
Garn slams Reagan for showing "no leadership in space whatsoever". Stofan,
NASA station admin, says Station may suffer from same up-and-down budget
that plagued the Shuttle. He says this is "devastating and wasteful" and
may double the cost of the program. [Lordy, considering what it already
costs...] Stofan says he will recommend scrapping the station if the
budget is too low, but refuses to say just how low that is.
Martin Marietta receives USAF contract for 13 more Titan 4s.
Canada and US reach agreement on Canadian space-station participation!
Amroc begins to recall work force after major new investor found.
Article on Galileo's latest trajectory, arrival at Jupiter 7 Dec 1995
from launch Oct 1989, with flybys of two asteroids (Gaspra and another,
name not mentioned) plus Venus and Earth. Plans underway for Venus
and Earth observations, including first infrared mapping of lunar farside.
The launch window is about 45 days long; failing that, July 1991 is possible
although the asteroid flybys would have to be shelved. Galileo is at JPL
with instruments starting to return from sponsoring labs. Full assembly
will be followed by thermal testing in summer, after which some instruments
will again go back home for final calibration before final assembly in
mid-1989. Modifications for the new schedule and trajectory include more
sunshades [Galileo originally not having been intended to get as close to
the Sun as Venus], a Sun sensor to ensure that Galileo can stay in its
"shaded" position without help from Earth, an aft-facing low-gain antenna
for inner-solar-system operation, a higher-performance telemetry encoder,
and isotope heaters replacing some electrical heaters on cold-sensitive
subsystems. The last two changes are aimed at preserving full operation
despite the loss in power caused by the delays [Galileo's isotope generators
cannot be refuelled at any reasonable price -- the plant that made them has
shut down -- and they will be about 12% of the way down their decay curve
due to the long delays in the mission]. Also underway is a study of the
shelf life and aging of systems and components, and various minor upgrades
in equipment that have become possible since it was built.
Soviet Union expected to unveil a plan for a space-based global aviation
navigation and tracking system at a spring meeting of ICAO's future-
navigation-systems group. Soviets continue unwilling to discuss status of
their Navstar lookalike, but make positive noises about sharing it with
others.
[Part 2 of the saving-the-space-station editorial is postponed to next time.
Instead we will observe three minutes of silence. Today is the anniversary
of Apollo 1. Tomorrow is the anniversary of Challenger. Last month,
slightly under two years after Challenger, the schedule for the first
post-Challenger shuttle launch slipped again, for at least the fourth
time. The most optimistic date is eight months from now. Slightly under
two years after Apollo 1, the first manned Saturn V took humans into deep
space for the first time, as Apollo 8 rounded the Moon... eight months
before Apollo 11. The three minutes of silence are for Grissom, White, and
Chaffee, for Scobee, Smith, McNair, Onizuka, Resnik, Jarvis, and McAuliffe...
and for the US space program that once was.]
--
Those who do not understand Unix are | Henry Spencer @ U of Toronto Zoology
condemned to reinvent it, poorly. | {allegra,ihnp4,decvax,utai}!utzoo!henry