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From: gsh7w@astsun.astro.Virginia.EDU (Greg Hennessy)
Newsgroups: sci.astro,sci.space,sci.space.shuttle
Subject: ASTRO status at 3/11:48 MET
Message-ID: <1990Dec5.183857.2736@murdoch.acc.Virginia.EDU>
Date: 5 Dec 90 18:38:57 GMT
Sender: news@murdoch.acc.Virginia.EDU
Organization: University of Virginia
Lines: 38

The situation on ASTRO continues to improve, but is by no means as
good as possible. BBXRT is observing, and getting almost all of its
data, although there was a temporary glitch of the Two Axis Pointing
System (TAPS). HUT works well, but has still not aquired any targets.
It has observed 10 objects that WUPPE aquired when WUPPE was primary,
or by manuan acquisition, and gotten VERY nice data. WUPPE has
observed 10 objects, and has one exciting result already, even before
the instrumental polarization is fully finished. There is a well known
dip in UV spectra around 2300 angstroms, which is attributed to
graphite, probably in dust grains. The question is wheter or not the
light is scattered off the grains, or absorbed by the grains. This all
was pointed out 25 years ago by Ted Stecher, the PI of the UIT
telescope. If the light was being absorbed, the polarization would not
be changed, but if the light was scattered, there would be a large
polarization induced into the starlight. The WUPPE team found that the
polarization did NOT change across the line, meaning that the light is
being absorbed not scattered. The UIT telescope made five long
exposures, and 3 short ones. There long observations included the
Perseus cluster, NGC2992, and the Crab Nebula, and M87. 

The science teams are still not happy with  with the tracking. When
the star trackers acquire the stars, the stability is very nice, but
the trackers  often do not work. Another patch was uplinked last night
and another test will be this shift. 

On shift four there was 0 percent of science being done, on shift five
there was 17, and on shift six there was 35 percent. However that 35
percent counted the time lost for a test as the star trackers as zero
time achieving science, but took in the time. If you only consider the
times that the teams attempted to observe, then the teams achieved 44
percent. The mission is being replanned to take longer exposures, so
better data of fewer objects will be done. 

--
-Greg Hennessy, University of Virginia
 USPS Mail:     Astronomy Department, Charlottesville, VA 22903-2475 USA
 Internet:      gsh7w@virginia.edu  
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