Status Report

NASA Hubble Space Telescope Daily Report #4863

By SpaceRef Editor
June 15, 2009
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HUBBLE SPACE TELESCOPE – Continuing to collect World Class Science


PERIOD COVERED: 5am June 9 – 5am June 10, 2009 (DOY 160/0900z-161/0900z)


ACS/WFC/S/C 11811

ACS CEB-R Optimization Iteration 3

During the early weeks of SMOV the ACS-R team will work to find the best parameters for CEB-R and the WFC CCD operations before continuing with the normal SMOV activities and eventually enable science operations. This optimization needs to be done in an iteratively way. The plan is to have up to eight iterations spread out through SMOV week 2-4. A core-set of observations aimed to assess the performance of the CCDs and to check the relative phasing between the internal ASIC signal and the incoming video signal will be repeated in all iterations. In any given iteration a specific test will be run to determine the best value for a given parameter. Data collected in each iteration will be quickly analyzed and if needed, new parameters will be uploaded in real time before the following iteration. The data will consist of a mix of normal data (bias, flat, EPER, darks) and O-mode data. In order to facilitate the program implementation, data collection and reduction, the program will be implemented in eight different proposals. 11811 covers the third iteration.

COS05/NUV 11466

NUV Detector Dark

Measure the NUV detector dark rate by taking long science exposures with no light on the detector. The detector dark rate and spatial distribution of counts will be compared to pre-launch data in order to verify the nominal operation of the detector, and for use in the CalCOS calibration pipeline. Variations of count rate as a function of orbital position will be analyzed to find dependence of dark rate on proximity to the SAA.

FGS 11458

Optimizing FGS2R2 Performance with the AMA

This proposal satisfies SMOV4 AD OTA/FGSS-054. S-curves with PUPIL and F583W will be obtained at selected locations within the FGS2R2 FOV during SMOV4. These data will be will be used to adjust the AMA so as to align the HST pupil onto the interferometer’s Koesters prisms. The final AMA position will be set to produce an acceptable set of S-curves across the FGS2R2 FOV. The AMA will be adjusted using CCL/instructions from the ground. It is intended that this proposal executes during the SMOV4 BEA and will require several (on the order of 4) iterations to achieve optimal interferometric performance.

STIS07/CCD 11404

CCD Dark and Bias Monitor for SMOV4/Cycle 17 Activity STIS-07

Monitor the darks for the STIS CCD. Monitor the bias in the 1×1, 1×2, 2×1, and 2×2 bin settings at gain=1, and 1×1 at gain = 4, to build up high-S/N superbiases and track the evolution of hot columns.

STIS18/MA2/S/C 11351

NUV MAMA HV Recovery

This proposal addresses the concerns over Cesium migration from the NUV-MAMA photocathode into the pores of the microchannel plate and lays out the procedures necessary to permit a safe and controlled recovery of the NUV-MAMA detector to science. This procedure should only be used during the SMOV4 high voltage recommissioning phase for the NUV-MAMA. After, the normal ramping procedure should be used. This proposal is loosely based on proposal 10036, STIS MAMA Anomalous Recovery, with the differences summarized below: (1) additional plateaus during voltage commanding, (2) longer dwells after each 50 V step, (3) intermediate ramp re-structured into 2 parts, (4) change in yellow and red limits and the MCP Hi limit, setting new values for the next plateau, and (5) adding a fold test at 300V below the nominal MCP voltage. The recovery consists of four separate procedures (visits) and they must be completed successfully and in order. They are: (1) a signal processing electronics check, (2) 1st high voltage ramp-up to an intermediate MCP voltage of -1500 V with limits modifications and voltage plateaus, (3) 2nd high voltage ramp-up to an intermediate MCP voltage of -1750 V (300 V below the nominal MCP voltage) with limits modifications and voltage plateaus followed by a fold distribution test, and (4) a final high voltage ramp-up to the full operating voltage, again with limits modifications and voltage plateaus, followed by a fold distribution test. During the 1st high voltage ramp-up, diagnostics are performed followed by a dark exposure. During the 2nd and 3rd high voltage ramp-ups, diagnostics are performed followed by a dark, flat field ACCUMs, and a fold analysis test. All required parameters are defined in 07-248 FUV and NUV SMOV Ramp-up Parameters Excel workbook. Supports Activity STIS-18

STIS19/MA1 11390

STIS-19 FUV MAMA Dark Measure

The STIS MAMA HV power supplies are turned on only during each day’s block of SAA-free orbits. The FUV MAMA dark current glow has been determined to increase with the length of time the FUV HV power supply has been on. The rate of this daily increase has changed over the years and also appears to be sensitive to temperature. To measure the rate at which the dark current increases, as soon as possible after the completion of STIS-17 (11350) completes a series of five 1380s FUV MAMA dark exposures spread over 5 or more orbits of a single SAA period will be taken. A second block of five exposures should be done near the end of the SMOV period when the temperature of the aft shroud and STIS are in the range expected for normal Cycle 17 operations.


Significant Spacecraft Anomalies: (The following are preliminary reports of potential non-nominal performance that will be investigated.)

HSTARS: (None)


18502-0 – Clear COS Event Flag 3 after FUV initial turn on Part 3-2 completes @ 160/1334z

18499-2 – Reconfigure to Avoid AD Closure Each Safemode @ 160/1358z

18503-0 – Clear STIS Event Flag 3 (MAMA2 Checkout Part 2) @ 160/1510z


1847-2 – Update COS FUV DCE HV Nom preset limits @ 160/1319z


FGS GSAcq 5 5
FGS REAcq 4 4
OBAD with Maneuver 4 4


Flash Report:

At GMT 160/13:05 the 486 and PSEA were reset to their nominal configuration to only command the aperture door closed for specific safemode event.

SpaceRef staff editor.