gsh7w@astsun.astro.Virginia.EDU (Greg Hennessy) (12/07/90)
Well, the last 24 hours has brought good news, extremely bad news, and now decent news. The good news was that during shift nine, the first 11 objects observed averaged 76 percent of the scheduled observing time, a value that made the science teams VERY happy. Most of the tracking was done by the astronauts by joystick, and obtained lots of data for the spectrometers. The patch to the star tracker did not clear the problem, but the automatic tracking was tried only three time, suceeding once, the first time it did suceed. The stability was excellent, and there was hope that the star trackers could be made to work before very long. Even the manual guiding gave respectable images for the UIT, which is most affected by loss of the star trackers. Observations were done of M100, M74, Hercules X-1, the Cygnus Loop, Alpha Hydra, the Vela SuperNova Remnant, and M82, among others. Then disaster struck. The second Data Display Unit (DDU) failed. This left the astronauts with no way to enter commands to the instruments. This meant that the UV instruments could not take any data whatsoever, even though BBXRT was unaffected. The day was understandable hectic, but a contingency plan has been developed. All the UV instruments have a backup ground based controls. During the past shift these instrumetns were powered up and tested. During this time the shuttle gave priority to BBXRT telescopes. Starting with shift 11, the data for the telescopes will be entered on teh ground, and uploaded. The astronauts will still do the manual guiding, but otherwise the UV instruments will be controlled on the ground. The science observations for shift 11 were canceled, and a system was iinstutued to first try to get UIT working, then HUT, then WUPPE. This was in order of decreasing field of view, or of increasing difficulty. This scenerio was never simulated, since loss of both DDU's was thought to be an unreasonable scenerio. UIT will pick two targets on opposite sides of the sky, NGC 1399 at Ra 3 hours 36 min and Centaurus A at Ra 13 hours 22 min. UIT will "ping-pong" back and forth between these two targets for 4 orbits, then HUT will try 2 orbits trying to acquire the quasar Q1821, then WUPPE will try 2 orbits trying to acquire GAM-GEM. On shift 12 other targets will be tried, or increasing scientific interest and degree of difficulty. These targets are still being worked out. Once confidence is gained in this mode of observing, secondary observations will be allowed. It now appears that a 10'th day of the mission is possible. Boy, was today hectic. -- -Greg Hennessy, University of Virginia USPS Mail: Astronomy Department, Charlottesville, VA 22903-2475 USA Internet: gsh7w@virginia.edu UUCP: ...!uunet!virginia!gsh7w
mac@idacrd.UUCP (Robert McGwier) (12/08/90)
From article <1990Dec6.230645.27668@murdoch.acc.Virginia.EDU>, by gsh7w@astsun.astro.Virginia.EDU (Greg Hennessy): > Well, the last 24 hours has brought good news, extremely bad news, and > now decent news. The good news was that during shift nine, the first > Just another example of when you should NOT send a man to do a robot's job. From the exercises fouling up the stability to lint from uniforms clogging air intakes, to residue from the huge thrusters (which are only necessary because it is a huge plane carrying men and the HEAVY life support equipment) the evidence is overwhelming that good science in astronomy done from orbit and human presence don't mix. The entire astro concept made no sense after they spent umpty dumpty million dollars and then refused to fly it but once. If they fly it again, its cost MIGHT come close to being justified. While I am on a roll, there is a statement of profound significance in the scientists remarks concerning 3C273 "I've waited 13 and a half years . . . ." We bellyache constantly in the US about the constant advances by the Japanese and Germans and then do not give adequate support to doing basic science and basic technology research. It is pitiful. Bob -- ____________________________________________________________________________ My opinions are my own no matter | Robert W. McGwier, N4HY who I work for! ;-) | CCR, AMSAT, etc. ----------------------------------------------------------------------------
gsh7w@astsun.astro.Virginia.EDU (Greg Hennessy) (12/10/90)
In article <828@idacrd.UUCP> mac@idacrd.UUCP (Robert McGwier) writes:
#Just another example of when you should NOT send a man to do a robot's job.
#From the exercises fouling up the stability to lint from uniforms clogging
#air intakes, to residue from the huge thrusters (which are only necessary
#because it is a huge plane carrying men and the HEAVY life support equipment)
#the evidence is overwhelming that good science in astronomy done from
#orbit and human presence don't mix.
Perhaps you are unaware that for the last four days the astronauts
were guiding the instruments because the "robot" was broken?
Perhaps you are unaware that this guiding CANNOT be done from the
ground because of the round trip travel time?
The entire astro concept made no sense
#after they spent umpty dumpty million dollars and then refused to fly
#it but once. If they fly it again, its cost MIGHT come close to being
#justified.
Please, by all means, write your congresscritter about ASTRO and write
NASA about it. If NASA and congress see public interest, ASTRO WILL
fly again. I expect that the images from UIT will be available to the
press in early January, and I will try to post FITS images to the net,
although I'll have to worry about the bandwidth.
#. . . ." We bellyache constantly in the US about the constant advances
#by the Japanese and Germans and then do not give adequate support to
#doing basic science and basic technology research. It is pitiful.
If you think it is pitiful, write to your congresscritter. If you are
not part of the solution, you are part of the problem. (Or part of the
precipate.)
--
-Greg Hennessy, University of Virginia
USPS Mail: Astronomy Department, Charlottesville, VA 22903-2475 USA
Internet: gsh7w@virginia.edu
UUCP: ...!uunet!virginia!gsh7wrose@beowulf.ucsd.edu (Dan Rose) (12/11/90)
mac@idacrd.UUCP (Robert McGwier) writes: >Just another example of when you should NOT send a man to do a robot's job. >From the exercises fouling up the stability to lint from uniforms clogging >air intakes, to residue from the huge thrusters (which are only necessary >because it is a huge plane carrying men and the HEAVY life support equipment) >the evidence is overwhelming that good science in astronomy done from >orbit and human presence don't mix. The entire astro concept made no sense >after they spent umpty dumpty million dollars and then refused to fly >it but once. If they fly it again, its cost MIGHT come close to being >justified. Well, all I know about ASTRO is what I read here and in the papers, but wouldn't the mission have been a total waste without the astronauts helping out with the star tracking duties? I thought this was evidence *for* human presence, not against it. (I realize that the lint might not have been there, but something else might have gone wrong, as with HST, Magellan, etc.) -- Dan Rose {ucbvax,decvax,akgua,dcdwest}!sdcsvax!beowulf!rose.uucp UC San Diego rose%cs@ucsd.edu