Status Report

Hubble Space Telescope Daily Repoert #2979 – 18 Oct 2001

By SpaceRef Editor
October 18, 2001
Filed under , ,

HUBBLE SPACE TELESCOPE

DAILY REPORT #2979

PERIOD COVERED: 0000Z (UTC) 10/17/01 – 0000Z (UTC) 10/18/01

Daily Status Report as of 291/0000Z

1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:

1.1 Completed Eleven 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 8369 and yesterday’s
report, the acquisition for the fifth iteration of this proposal defaulted
to fine lock backup on one FGS only, possibly affecting the observations in
this iteration. Then, as described in HSTAR 8370 and 2.1, the acquisition
for the final iteration of this proposal failed, the take data flag
remained down, and two observations were lost. Otherwise, the observations
completed with no further anomalous activity.

1.2 Completed STIS/MA1 8561 (The Ionizing Flux from Star-Forming Galaxies)

The Space Telescope Imaging Spectrograph (MA1) was used to measure
the meaningful upper limits on the amount of ionizing radiation from
galaxies in the current epoch. The proposal completed nominally.

1.3 Completed Six Sets of 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. The proposal had no problems.

1.4 Completed Three 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.

1.5 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.

1.6 Completed Two 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. As described in HSTAR 8369 and yesterday’s report,
the acquisition for this proposal defaulted to fine lock backup on one FGS
only, possibly affecting the observations. Otherwise, no further problems
occurred.

1.7 Completed STIS/CCD/MA2 9048 (Boron Constraints on Slow Mixing in
Low Mass Stars)

The Space Telescope Imaging Spectrograph (CCD and MA2) was used to
observe the atomic and nuclear characteristics of the light elements Li, Be
and B, that make their photospheric abundances ideal tracers of internal
physical processes in stars. Both Li and Be have been heavily utilized to
this end since their diminished abundances are a direct result of the
extent of internal slow mixing between surface and interior layers, as has
been shown with ground-based data. Boron provides a fresh and special
probe because it survives to greater depths inside stars than does Li or
Be, and can thus uniquely reveal the depth of mixing. It is proposed to
observe B in stars with very large depletions of Li and Be, i.e. stars
which have been the most seriously affected by mixing. No problems occurred.

1.8 Completed STIS/CCD/MA2 8569 (A New Survey for Low-Redshift Damped
Lyman-Alpha Lines in QSO MgII Systems)

The Space Telescope Imaging Spectrograph (CCD and MA2) was used to
support studies which have shown that most of the observable neutral gas
mass in the Universe resides in QSO damped LyAlpha {DLA} systems. However,
at low redshift, DLA can only be found by searching in the UV with HST. By
boot-strapping from the MgII statistics, we will be able to further improve
the determination of the low- redshift statistical properties of DLA {their
incidence and cosmological mass density} and open up new opportunities for
studies at low redshift. The observations completed nominally.

1.9 Completed STIS/CCD 9148 (Light Echos and the Nature of Type Ia
Supernovae)

The Space Telescope Imaging Spectrograph (CCD) was used to take
STIS snapshot images of a subset of 43 well observed Type Ia supernovae
{SNIa}, most of which have been discovered in late type galaxies over the
last 40 years to make a systematic search for light echos around SN
Ia. STIS will also observe a sample of 10 SN II and SN Ib/c, which are
believed to be the result of massive star core collapse and, therefore, to
be thin-disk population objects, in order to make an empirical calibration
of the accuracy of our method for determining scale heights. The SN Ia
sample will provide a direct as well as accurate estimate of the scale
height of SN Ia which is an important clue to the progenitors of these
events. The proposal completed nominally.

1.10 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.

1.11 Completed 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.

1.12 Completed STIS/CCD 9143 (Spectrophotometry of Nearby Seyfert 2
Nuclei: Can We Eliminate the Seyfert 2 Class?)

The Space Telescope Imaging Spectrograph (CCD) was used to
investigate Seyfert 2s that are distinguished by the absence of the broad
emission lines characteristic of Seyfert 1s and more luminous QSOs. Are
Seyfert 2s fundamentally different from Seyfert 1s and their brighter
cousins? Or is the broad emission line region in Seyfert 2s simply
suppressed by obscuring material as postulated by the unification
model? If the latter model is correct, the weak broad emission lines in
the Seyfert 2s may simply be overwhelmed by starlight from the
circumnuclear region, particularly in the case of recent star
formation. It is proposed to determine if all Seyfert 2s have {weak} broad
emission line regions by obtaining long-slit STIS spectroscopy for a
well-defined sample of 20 Seyfert 2s {3 archival, 17 new}. The
observations completed with no anomalous activity.

1.13 Completed Two Sets of STIS/CCD 9077 (Survey of the LMC Planetary
Nebulae)

The Space telescope Imaging Spectrograph (CCD) was used to perform
a snapshot survey of all known LMC planetary nebulae {PNe} in order to
study the co-evolution of the nebulae and their central stars, and to probe
the chemical enrichment history of the LMC. As described in HSTAR 8370 and
2.1, the acquisition for the second iteration of this proposal failed, the
take data flag remained down, and the observation was lost. Otherwise,
there were no additional problems.

1.14 Completed STIS/CCD 9176 (LMC Eclipsing Binaries with Cepheid
Components: The Key to the Extragalactic Distance Scale)

The Space Telescope Imaging Spectrograph (CCD) was used to
determine the distance to the LMC and to observe the Cepheid P-L that form
the backbone of the Cosmic Distance Scale and the determination of
H_degrees. Unfortunately, in spite of concerted efforts of many
investigators, the zero point of the Cepheid P-L law and the LMC distance
remain controversial and uncertain to ~10-15, using eclipsing binaries
{EBs} as “standard candles” to include two recently discovered LMC
eclipsing binaries {EBs} with Cepheid components. These observations of
these extraordinary systems hold the key to determining simultaneously the
Cepheid P-L zero point and the LMC distance, and to provide a direct test
of the Baade-Wesselink parallax method. There were no reported problems.

1.15 Completed Two Sets of WF/PC-2 8059 (POMS Test Proposal: Targeted
Parallel Archive Proposal)

The WF/PC-2 was used to observe the parallel opportunities
available in the neighborhood of bright galaxies are treated in a slightly
different way from the normal pure parallels. Local Group galaxies offer
the opportunity for a closer look at young stellar
populations. Narrow-band images in F656N can be used both to identify
young stars via their emission lines, and to map the gas distribution in
star-forming regions. The observations completed nominally.

1.16 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.

1.17 Completed STIS/CCD/MA2 9116 (Understanding High-Redshift and
Starburst Galaxies: A UV Spectroscopic Survey of B- Stars in the SMC)

The Space Telescope Imaging Spectrograph (CCD and MA2) was used to
construct a high quality spectral library at low metallicity in order to
synthesize the UV spectra of high redshift star-forming galaxies and nearby
starbursts. No problems were reported.

2.0 FLIGHT OPERATIONS SUMMARY:

2.1 Guide Star Acquisitions:

Scheduled Acquisitions: 11

Successful: 10.

As detailed in HSTAR 8390, the acquisition scheduled for
290/214435Z failed when the search radius limit was exceeded. A subsequent
map showed relatively small errors. The proposals described in 1.13 and
1.1 were affected.

Scheduled Re-acquisitions: 7

Successful: 7

2.2 FHST Updates:

Scheduled: 13

Successful: 13

2.3 Operations Notes:

Using ROP SR-1A, the SSR EDAC error counter was cleared three times.

The STIS MCE-2 reset at 290/113209Z while the low voltage was on
and while inside an SAA interval. The STIS flight software error counter
was reset at 290/1213Z as directed by ROP NS-12. MAMA-2 was recovered at
290/2240Z, the time of the next high voltage on commanding in the SMS.

SSR-3 was powered on and configured for an on-orbit test. The TRI
module was re-configured at 290/1509Z per ROP SR-9A. SSR-3 performance
verification was successfully performed at 290/1512Z per an operations
request. Finally, dual SSR procedures were loaded onto the CCS system at
290/1930Z.

The engineering status buffer limits were adjusted at 290/2152Z per
ROP DF-18A.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

Continuation of normal science observations and calibrations.

SpaceRef staff editor.