Status Report

Hubble Space Telescope Daily Report #2956 -14 Sep 2001

By SpaceRef Editor
September 14, 2001
Filed under , ,

HUBBLE SPACE TELESCOPE

DAILY REPORT #2956

PERIOD COVERED: 0000Z (UTC) 09/13/01 – 0000Z (UTC) 09/14/01

Daily Status Report as of 257/0000Z

1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:

1.1 Completed Five Sets of WF/PC-2 9244 (POMS Test Proposal: WFII
Parallel Archive Proposal Continuation)

The WF/PC-2 was used to perform a generic target version of the
Archival Pure Parallel program. The program will be used to take parallel
images of random areas of the sky, following the recommendations of the
Parallels Working Group. As described in HSTAR 8339 and 2.1, the
acquisition for the third iteration of this proposal defaulted to fine lock
backup on one FGS only, possibly affecting one observation. Otherwise, the
observations completed with no further anomalous activity.

1.2 Completed Two Sets of STIS/CCD 8901 (Dark Monitor-Part 1)

The Space Telescope Imaging Spectrograph (CCD) was used to monitor
the darks. There was no anomalous activity.

1.3 Completed Four Sets of WF/PC-2 8936 (Cycle 10 Supplemental Darks Pt1/3)

The WF/PC-2 was used to perform a dark calibration program that
obtains three dark frames every day to provide data for monitoring and
characterizing the evolution of hot pixels. The proposal completed with no
reported problems.

1.4 Completed WF/PC-2 8584 (Calibrating the Metallicity Dependence of
the Cepheid PL Relation)

The WF/PC-2 was used to determine the uncertainty in the metal
abundance dependence of the Cepheid PL relation that remains as one of the
largest sources of systematic error in the Cepheid distance scale and in
the extragalactic distance scale as a whole. There were no reported problems.

1.5 Completed STIS/CCD 9285 (POMS Test Proposal: STIS Non-scripted
Parallel Proposal Continuation III)

The Space Telescope Imaging Spectrograph (CCD) was used to make low
galactic latitude, non-scripted parallel observations as part of a POMS
test proposal. The observations were completed as planned, and no
anomalies were reported.

1.6 Completed STIS/CCD 9051 (Identifying Damped Lyman-alpha Galaxies at
z~1)

The Space Telescope Imaging Spectrograph (CCD) was used to look for
samped Lyman-alpha absorption systems that contain the bulk of the neutral
gas in the Universe in the redshift range z = 0.5 – 5, yet the nature of
the galaxies responsible for the absorption is not well understood. Only
recently have observers found more than a handful of damped absorbers at
redshifts z < 1.5. Using the FIRST Bright Quasar Survey {FBQS}, with over a 1000 quasars, the proposers have undertaken a survey to build a complete picture of he nature of the galaxies responsible for damped Lyman-alpha absorption systems at z~1 and to double the sample size at this redshift. No problems were encountered.

1.7 Completed STIS/CCD 8903 (Bias Monitor – Part 1)

The Space Telescope Imaging Spectrograph (CCD) was used to 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. There were no problems.

1.8 Completed WF/PC-2/STIS/CCD 9174 (Using Optically Faint Radio
Sources to Pinpoint Dusty Proto-Galaxies)

The WF/PC-2 and the Space Telescope Imaging Spectrograph (CCD) were
used to observe a number of high redshift, dusty starburst galaxies that
remain invisible in ground based in the Hubble Deep Field. These galaxies
appear as faint radio sources with bright submillimeter counterparts,
demonstrating they are very dusty systems. The luminosities of these
galaxies suggest they are in the process of converting the bulk of their
gas mass into stars, and will likely evolve into present day massive
ellipticals. The observations completed normally, with no reported problems.

1.9 Completed STIS/CCD 9136 (T Tauri Star Coronagraphic Survey: A PMS
Protoplanetary Disk Census)

The Space Telescope Imaging Spectrograph (CCD) was used to observe
pre-main sequence solar-mass stars, the T Tauri stars that Millimeter and
IR studies suggest at least 50 percent have circumstellar disks similar to
the disk from which our planetary system formed. High spatial resolution,
high dynamic range imaging of such systems will map the spatial
distribution of material around the star, constraining the disk sizes and
inclinations, and provide a first assessment of when structure in the disk,
such as cleared central zones and annuli, which has been linked to planet
formation, develops. As described in HSTAR 8339 and 2.1, the acquisition
for this proposal defaulted to fine lock backup on one FGS only, possibly
affecting five observations. Otherwise, all observations completed without
incident.

1.10 Completed WF/PC-2 8941 (Cycle 10 UV Earthflats)

The WF/PC-2 was used to monitor flat field stability by obtaining
sequences of earth streak flats to improve the quality of pipeline flat
fields for the WFPC2 UV filter set. As described in HSTAR 8339 and 2.1,
the acquisition for this proposal defaulted to fine lock backup on one FGS
only, possibly affecting two observations. Otherwise, the proposal had no
other problems.

1.11 Completed Three Sets of STIS/CCD 9088 (Next Generation Spectral
Library of Stars)

The Space Telescope Imaging Spectrograph (CCD) was used to produce
a “Next Generation” Spectral Library of 600 stars for use in modeling the
integrated light of galaxies and clusters by using the low dispersion UV
and optical gratings of STIS. The library will be roughly equally divided
among four metallicities, very low {Fe/H < -1.5}, low {-1.5 < Fe/H < -0.5}, near-solar {-0.5 < Fe/H < 0.1}, and super-solar {Fe/H > 0.1}, well-sampling
the entire HR-diagram in each bin. Such a library will surpass all extant
compilations and have lasting archival value, well into the Next Generation
Space Telescope era. No problems occurred.

1.12 Completed STIS/CCD 8911 (Sparse-Field CTE External C10)

The Space Telescope Imaging Spectrograph (CCD) was used to
determine the derivation of accurate coefficients which can be used to
correct low count level data {both imaging and spectroscopy} for
nonlinearity/CTE effects. Dependences on x-position, background sky level,
and time dependence will be quantified in addition to accurate
determination of intensity and y-position effects in a third epoch and to
higher accuracy than previously determined. The proposal completed with no
reported problems.

1.13 Completed Three Sets of WF/PC-2 9249 (POMS Test Proposal: WFII
Backup Parallel Archive Proposal II)

The WF/PC-2 was used to execute a POMS test proposal designed to
simulate scientific plans. The proposal completed with no reported problems.

1.14 Completed WF/PC-2 9160 (Disks and Envelopes of Nearby Nebulous
Young Stellar Objects: A Snapshot Survey)

The WF/PC-2 was used to perform a snapshot survey of nearby
nebulous young stellar objects to study the detailed morphology of the
their disks and envelopes and probe the effect of inclination on the
infrared spectral energy distribution of disk/envelope systems. The
proposal completed as planned.

1.15 Completed STIS/CCD/MA2 9040 (Baryons In Intermediate Redshift {Z >
1} OVI Absorbers)

The Space Telescope Imaging Spectrograph (CCD and MA2) was used to
search for intervening OVI absorption systems in two further extremely UV
bright intermediate redshift QSOs {HS 0747 + 4259, z = 1.9, V = 15.6; HS
0818+2554, z = 1.5, V = 15.4} using the STIS E230M Echelle mode. The
scientific aim is to measure the baryonic fraction in the warm-hot
intergalactic medium at redshifts 1 <=q z <=q 1.8. Present existing data on HE 0515-4414 taken also with STIS E230M seem to indicate that the baryonic fraction at z = 1.5 is lower by a factor of ~ 15 than the high value found by Tripp et al. {2000} for z < 0.3. Our results need to be confirmed by more lines of sight, and we plan to test hierarchical structure formation models which predict a rapid evolution between z = 1.5 and z = 0. The observations completed as planned with no reported anomalous activity.

2.0 FLIGHT OPERATIONS SUMMARY:

2.1 Guide Star Acquisitions:

Scheduled Acquisitions: 8

Successful: 8

Per HSTAR 8339, the acquisition at 256/115341Z defaulted to fine
lock backup on FGS-1 when the scan step limit was exceeded on FGS-3. The
science proposals detailed in 1.1, 1.9 and 1.10 may have been affected.

Scheduled Re-acquisitions: 6

Successful: 6

2.2 FHST Updates:

Scheduled: 17

Successful: 17

2.3 Operations Notes:

The SSR EDAC error counter was cleared twice, per ROP SR-1A.

A TTR Was generated when there was an engineering data loss from
256/1009Z until 256/1029Z due to bad weather.

An SSR engineering record was performed at 256/1032Z per ROP SR-4A.

The NSSC-1 status buffer was dumped and reset at 257/0507Z as
directed by ROP NS-3.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

Continuation of normal science observations and calibrations.

SpaceRef staff editor.