NOTE:  THE NEXT MEETING IS WEDNESDAY, MARCH 19, 8:30 AM.


STATUS REPORTS

1.  Observatory Status - All subsystems nominal

	MOSES reported that visits 5 and 6 of Proposal 7026 (FGS 1R
	FF3 Optimization) executed successfully and the data look
	good.  Analysis is continuing.

	
2.  WFPC2 Status - Proceeding nominally with Cycle 6 science and
	remaining SMOV monitors.  John Biretta circulated an
	email with the latest UV Monitor results:  the
	contamination rate shows signs of improving.  The email
	is attached.

	Pending Project approval, an OTA SM desorption move is
	planned for late tomorrow (3/18).  The proposed move,
	discussed in an STScI/HSTP telecon on Friday, is
	- 2.5 microns, thereby ensuring that the focus will
	stay within +/- 2 microns of its nominal position
	throughout SMOV.  (See same attached email)
	
3.  NICMOS Status

	- Engineering status - The Cold Well temperature is
	~60.2 degK and the rate of increase is ~0.1 deg/day.
	(These and similar rates of increase reported in previous
	meeting notes are actually down in the noise.)  
	The VCS temperature is now 101.2 degK and the
	rate of cooling is now -1.5 deg/day.  These trends
	remain in the right direction for stabilization.

	- Science Status - Because of continued expansion of
	the dewar, the Project accepted a recommendation from
	the STScI, NICMOS and BASD, to position a scientifically
	optimum set of filters in each camera and leave them
	there at least for the near term until dewar behavior
	is better understood.  Accordingly, over the weekend, the
 	the F110M was rotated into position for Camera 1, along
	with the F160W for Cameras 2 and 3.  A flight software
	flag was set to prevent any further filter wheel motions
	that would result from stored commanding in upcoming 
	activities.  This decision is strictly a
	precautionary one that mitigates the risk in case of any
	structural clearance problem in rotating the filter
	wheels.  Wednesday's activities (7135- Intermediate
	Alignment Test) will proceed as planned, although
	with filter motion prevented, the STOCC can expect to see
	status buffer messages resulting from the blocked
 	commands.  (The PAM updates needed, as planned, for
	7135 are being worked.)   The alignment tests 7135 and
	7042 (fine alignment) are expected to produce useful
	data with this filter configuration.


4.  STIS Status

	- Engineering Status - Nothing new to report.

	- Science Status - the CCD UV Monitor occurred as planned
	Saturday night;  results are not yet known.  The list
	of CCD "bad pixels" is being worked.


5.  FGS status - See MOSES reprt above.


6.  FOC/COSTAR status- no new activity
  

PLANNING REPORTS

1.  Status of Upcoming SMSs

   	- SMS076 - Currently executing.

  	- SMS072 - Signed off.

	- SMS076 - Final Mode products are out for review.  

	- SMS079 - Final mode products released to operations.
 
	- SMS083 - Initial Mode products are available for
		   review on AP7.  The new executable for the
		   MEGG fix is expected on Wednesday.

 		   This SMS implements the SSR for engineering
 		   data record.  This SMS also has been modified
 		   to include the Target of Opportunity
 		   identified lst week.

		 - The STIS SIAF PDB updates for this SMS will be
		   submitted in two segments, one for the first
 		   part of the SMS and one for later.

	- SMS090 - Initial calendar build has begun. SARs are
		   out.
	  	   A "10.2" commanding update is also needed for
		   this SMS.

	- SMS097 - Will start being built today.

	- SMS104 - Will require a "10.2 commanding update for
		   NICMOS SAA avoidance and for STIS CCD 
		   annealing process.  This update is on
 		   schedule.  The annealing proposal (7107) can
 		   go in this SMS.

2.  Replans

	STIS

	- MAMA HV Turn-on (7105) is delayed (from 21 March)
	  indefinitely.  Affects on downstream MAMA
	  scheduling will be assessed.

	NICMOS

	- None yet identified.

OPERATIONS STATUS

1.  OPUS - Nominal. OPUS is preparing for upcoming quick data
		turn-arounds for STIS UV monitor (7063) as
 		well as a "time-tag slew" needed for the
		as-yet-uncorrected aperture position offsets.
		NICMOS intermediate alignment (7135) will also
		need an FTP quick data turn-around, as will
	        the NICMOS/FGS Aperture Location Test (7039).  
		STIS ERO 7124 has also been modified to use
		a "re-use target offset" which OPUS will execute.

2.  Archive - Nominal.


ATTACHMENT  -- WFPC2 UV Monitor Update


WFPC2 SMOV UPDATE 
=================

15 March 1997 -- John Biretta


Latest UV Monitor Results
-------------------------

We obtained more data Thursday, and there is now
some evidence for a decline in the contamination
growth rate.  Prior to the latest data, the growth
rate averaged 70% higher than pre-SMOV across the
four CCDs, but with the latest data the rate averages
only 33% higher than pre-SMOV.  Here are the numbers
in terms of F170W throughput loss per day:

CCD        Pre-SM97             Current 
---     ---------------      -------------

PC1	0.53% +/- 0.04%	     0.8% +/- 0.1%
WF2	0.95%     0.02%      1.3%     0.1%
WF3	0.95%     0.02%	     1.2%     0.1%
WF4	0.77%     0.02%	     0.9%     0.1%

We'll be getting more data in the next few days.



Possible OTA Secondary Mirror (Focus) Move Next Week
-----------------------------------------------------

We've obtained much more focus data over the last two
weeks, and processed these through the usual phase
retrieval software.  The average focus position continues
to be about +4 microns (units of OTA secondary mirror
position), with the values scattering between about 
0 and +7 microns.  Meetings were held with the SSD and
SM97 instrument leads on 3/14, and a recommendation was
drafted and forwarded to the HST project office for 
an OTA secondary mirror move of -2.5 microns.  This
should bring average focus close to zero in May when
STIS and NIC perform their fine alignments.  The project
office will examine engineering aspects of the proposed
move, and may undertake to move the OTA secondary 
sometime next week.

 

biagetti@stsci.edu

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