Status Report

NASA Hubble Space Telescope Daily Report #4859

By SpaceRef Editor
June 9, 2009
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HUBBLE SPACE TELESCOPE – Continuing to collect World Class Science


PERIOD COVERED: 5am June 3 – 5am June 4, 2009 (DOY 154/0900z-155/0900z)


ACS/WFC/S/C 11810

ACS CEB-R Optimization Iteration 2

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. 11810 covers the second iteration.

COS/NUV/S/C 11355

COS NUV Initial On-Orbit Turn-On and Recovery after Anomalous Shutdown

This proposal is designed for the initial turn-on of the COS NUV MAMA detector. The same procedure may later be used to recover the detector after an anomalous shutdown. Anomalous shutdowns can occur as a result of bright object violations which trigger the Bright Scene Detection or Software Global Monitor. Anomalous shutdowns can also occur as a result of MAMA hardware problems. The Initial MAMA turn-on consists of three tests: a signal processing electronics check; a slow high voltage ramp-up to an intermediate voltage; and a slow high voltage ramp-up to the full operating voltage. During each of the two high voltage ramp-ups, diagnostics are performed during a dark time-tag exposure. The turn-on is followed by a MAMA Fold Analysis Test. The complete sequence is contained in visits 1 through 4. If a second execution is required during cycle 17, visits 5 through 8 will be run and another proposal prepared for possible future occurrences.

Supports Activities COS-04 and COS-07

FGS/S/C 11458

Optimizing FGS2R2 Performance with the AMA

Ths 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.

STIS06/CC 11382

STIS SMOV4 CCD Functional

This proposal corresponds to the SMOV4 activity summary, STIS06.

This purpose of this activity is to measure the baseline performance and commandability of the CCD subsystem.

This test assesses several CCD functions and performance characteristics, including: bias levels, read noise, dark current, CTE, and gain. Bias, dark, and flat field exposures are executed to achieve these goals. Full frame and binned (2 x 1, 1 x 2, and 2 x 2) observations are made. Biases are taken at gain=1 and read-out in subarray mode to support target acquisition and peakup modes.

Only the primary amplifier (Amp D) is used. Dark exposures are made outside the SAA (as is standard). All exposures are internals

STIS07/CC 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.

STIS08 11383

STIS SMOV4 Aperture Wheel and Lamp Functional Tests (activity STIS08)

This SMOV4 Phase2 proposal corresponds to SMOV4 activity summary, STIS-08.

This is activity has five functions: verification of the aperture positions, verification of absolute optical position, verification of slit wheel repeatability, verification of lamp functionality, and verification of CCD imaging mode functionality.

STIS09/CC 11384

STIS-09 STIS to FGS Alignment

This visit will measure the alignment between the STIS instrument CCD and the HST FGSs by taking dithered STIS 50CCD images of a star with highly accurate astrometric positions (UCAC-2, or Tycho, or Hipparcos or better) to determine STIS CCD to FGS offset and rotation angle. The guide stars used should have astrometric accuracy comparable to that of the target. Interleaving external images and lamp images of a reference slit will ensure that external target is properly registered with respect to the STIS aperture plane. This test is intended to be conducted during the BEA (bright earth avoidance) period, so sufficient targets and contingency visits are defined to ensure that there are always available targets in both the northern and southern BEA zones during the SMOV period.

STIS10 11385

STIS-10 CCD Optical Format Verification

This proposal will take a lamp spectrum at a single CENWAVE setting of each of the CCD spectroscopic optical elements, G230LB, G230MB, G430L, G430M, G750L, and G750M. The exposures here are repeats of selected exposures that were taken in June 2001 as part of the Cycle 11 CAL/STIS program 9617. The location of each spectrum on the detector will be compared with the pre-repair observations, to look for operationally signficant shifts. The observed line-widths will also be compared with the previous observations to look for any changes in spectral resolution.

STIS14/CC 11400

STIS CCD CTI Check: STIS Activity Number STIS-14

For CCD detectors, the transfer of charge from one pixel to the next is not perfect. Charge Transfer Inefficiency (CTI) measurements quantify the fraction of charge left behind after this charge transfer. The further the charge needs to be shifted before the read-out, the more charge it will lose. Therefore, CTI measurements are necessary and can be determined through the “internal sparse field test”. CTI measurements are made along the parallel axis and used in conjunction with the following optional parameter POS which allows the off-center positioning of the MSM for some slits. This activity is the first in a series of measurements that will be made to characterize the dependence of the CCD CTI as a function of signal level, source position, and time. The remaining measurements will be conducted as part of the Cycle 17 calibration program to fully characterize the CTI. This activity, executed during the SMOV4 period, will enable measurement of the magnitude of the CTI for a limited parameter set and will provide a comparison of the current CTI performance with the CTI performance prior to the Side-2 failure. All exposures are internals.

STIS17/MA/S/C 11350

FUV MAMA HV Recovery

This proposal addresses the concerns over Cesium migration from the FUV-MAMA photocathode into the pores of the microchannel plate and lays out the procedures necessary to permit a safe and controlled recovery of the FUV-MAMA detector to science. This procedure should only be used during the SMOV4 high voltage recommissioning phase for the FUV-MAMA. After that, the normal ramping procedure should be used. This proposal is loosly 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 and unique 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 -1950 V (300 V below the nominal MCP voltage) with limits modifications and voltage plateaus followed by a fold distribution test, and (4) the 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-17

STIS5/CC 11399

STIS CCD Hot Pixel Annealing (SMOV4 activity STIS-05)

This purpose of this activity is to repair radiation induced hot pixel damage to the STIS CCD by warming the CCD to the ambient instrument temperature and annealing radiation damaged pixels.

Radiation damage creates hot pixels in the STIS CCD Detector. Many of these hot pixels can be repaired by warming the CCD from its normal operating temperature near -83 deg C to the ambient instrument temperature (~ +5 deg C) for several hours. The number of hot pixels repaired is a function of annealing temperature. So although the CCD during Safing has been warmer (~ -5 deg C) than its normal operating temperature, the electronics have been off and the CCD has remained cooler than its temperature (+5 deg C) during the annealing procedure.

The effectiveness of the CCD hot pixel annealing process is assessed by measuring the dark current behavior before and after annealing and by searching for any window contamination effects. In addition CTE performance is examined by looking for traps in a low signal level flat. This proposal is a continuation of the Cycle 12 proposal 10022.


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

HSTARS: (None)




FGS GSAcq 9 9
FGS REAcq 0 0
OBAD with Maneuver 6 6


Flash Report:

Part 3 of the COS NUV init turn-on was completed today at 154 19:00:10.

SpaceRef staff editor.