To:sot_shift
from: Dan Schwartz
date: 1 Aug 99, 0825 EDT
Subject: SOT shift report, Shift A10
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See http://asc.harvard.edu/acis/SOT_reports/sot-shift.html, or 
/proj/ascwww/AXAF/extra/science/htdocs/acis/SOT_reports/July_30_1999_B.txt.


Shift A10. 
	Start at 213:01:00  GMT
		 = 0900 pm 31 July 99
	End	    9:20am 1 Aug
   
SOT Lead	DAS
Spac/Aspect	RAC
FOT/Sci liason	EM
HRC		SSM,EJ 
ACIS 		PPP,RB,FB,MB

(Times will be given in GMT on day 213. In general
times are rough, not precise.)

PLAN
Perform earth scan #16. DONE
Measure Vacuum monitor. DONE
ACIS internal calibration source measurements.
Run Cap 129 to recover fid light tracking.
Run Cap 135 to complete series of tests of SIM flexure heating
  


EVENTS
Telemetry has OBSID 62482 as expected, at start of shift.

Run CAP 129 to recover fid light tracking, at ~01:30

SSR playback, started ~02:07.

Run CAP 70 to re-enable RADMON. 03:46.

03:50, maneuver out of the earth scan 16. 

OBSID 62741 at 04:51, for first of series of ACIS internal 
cal source measurements. 
Change to Format 2. Focal plane temperature is -118.9, 04:55.
OBSID 62740 at 05:22
OBSID 62739 at 
We do NOT plan to use OBSID 62738 because we are only running
   three cases of the internal cal source measurement.

Turn on vacuum monitor at 05:48. Pressure reads 10^-5 torr.
Drops to 9.7 10^-6 at 10:53.

Ground station handover about 07:50 (Goldstone to Canberra).

Start pitch to 65 deg for flexure heating tests, 09:10.

Lose fid light in slot 5, the faintest fid light, ~08:00.

NOTES/ISSUES/PROBLEMS
Set up for CAP 93A, which is the modified radiation belt
sequence used at the lower perigees.  We expect NOT to 
actually use this, since IPS-4 should raise perigee to 
the final value prior to the next perigee passage.

Clash of SCS slots. ACIS used 143, but pitch to sun point
also used it and had it enabled and activated and at a 
step number beyond where ACIS was using it. So ACIS now
has to skip the disabling of the 143 slot, so that the 
spacecraft can continue to use it. 

Prepare a Patch request for a patch to the ACA flight 
software to prevent loss of lock when a single cosmic
ray track hits an image. Need date identified as start
of OAC Phase 2.

Prepare a Patch request for the OBC to reacquire all fid
lights at 1000 sec intervals (whether they are lost or 
not). This backstops the above desired patch to the ACA
software which is intended to prevent loss of lock. 

Data recovery. There were puzzles concerning the SSR data
from 211:05:23 to 211:13:31.  This data was "lost" (put 
in the wrong directory?) for about 2 days, apparently without
GOT or ascds DutyScientists raising alarms. Then the 
GOT reported irretrievably bad data quality, whereas our
SOT examination of the IDR files ftp'ed from JPL showed
perfect data.  This particular data was of interest
in relation to understanding how to make ACIS bias maps
in the presence of cosmic rays.

PCAD quick look following two different pitch maneuvers showed
extremely low residual rates -- no more than a few hundredths
arcsec per sec. This probably indicates very small effects due 
to slosh.

Apogee following IPS-3 was reported as 139,100 km.
-------------------------------------------------------
Dan Schwartz,	MS #3
das@head-cfa.harvard.edu  
phone: (617)495-7232    FAX:   (617)495-7356
cell phone: (617)512-5627   
pager: 800-759-8352 PIN 1636502
       or e-mail 1636502@skytel.com 
-------------------------------------------------------