Status Report

Hubble Space Telescope Daily Report #2967 – 1 Oct 2001

By SpaceRef Editor
October 1, 2001
Filed under , ,

HUBBLE SPACE TELESCOPE

DAILY REPORT #2967

PERIOD COVERED: 0000Z (UTC) 09/28/01 – 0000Z (UTC) 10/01/01

Daily Status Report as of 274/0000Z

1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:

1.1 Completed STIS/CCD 8928 (PSFs at Pseudo-Apertures {Cycle 10})

The Space Telescope Imaging Spectrograph (CCD) was used to perform
spectroscopic PSF measurements, performed for the new pseudo-apertures
located near CCD row 900, which are made available to ameliorate CCD CTE
losses. The proposal completed nominally.

1.2 Completed Six 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.

1.3 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 2.1 and HSTAR 8355, the
acquisition for the eighth iteration of this proposal defaulted to fine
lock backup one FGS only, possibly affecting all observations in that
iteration. Otherwise, the observations completed with no other anomalous
activity.

1.4 Completed Six 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.

1.5 Completed WF/PC-2 9256 (Methane Quad Filter Check)

The WF/PC-2 was used to verify the FQCH4N-D methane filter
characteristics. The proposal completed nominally.

1.6 Completed Three Sets of 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.

1.7 Completed Nine Sets of STIS/CCD 9066 (Closing in on the Hydrogen
Reionization Edge of the Universe)

The Space Telescope Imaging Spectrograph (CCD) was used in parallel
constrain the Hydrogen reionization edge in emission that marks the
transition from a neutral to a fully ionized IGM at a predicted
redshifts. As described in 2.1 and HSTAR 8355, the acquisition for the
seventh iteration of this proposal defaulted to fine lock backup one FGS
only, possibly affecting all observations in that iteration. Otherwise,
the proposal completed uneventfully.

1.8 Completed Six Sets of FGS/1 9167 (Astrometry of the Extrasolar
Planet of Epsilon Eridani)

Fine Guidance Sensor #1 was used in position mode to determine the
astrometric elements {perturbation orbit semimajor axis and inclination} of
the candidate extra-solar planet around the K2 V star Epsilon Eridani that
has been detected by Dopler spectroscopy. These observations will also
permit determination of the actual mass of the planet by providing the
sin{i} factor which can not be determined with the radial velocity
method. There was no anomalous activity.

1.9 Completed FGS/1 9034 (The Masses and Luminosities of Population II
Stars)

Fine Guidance Sensor #1 was used to observe the mass-luminosity
relation {MLR} of Population II stars of which very little is currently
known. With the advent of the Hipparcos Catalogue, improved distances to
many spectroscopic binaries known to be Pop II systems are now
available. After surveying the literature and making reasonable estimates
of the secondary masses, we find 13 systems whose minimum separation should
be larger than the resolution limit of FGS #1. As described in 2.1 and
HSTAR 8355, the acquisition for this proposal defaulted to fine lock backup
one FGS only, possibly affecting all observations. Otherwise, the
observations completed nominally.

1.10 Completed Two Sets of WF/PC-2/STIS/CCD 8573 (Newborn Planets and
Brown Dwarf Companions in IC 348)

The WF/PC-2 and the Space Telescope Imaging Spectrograph (CCD) were
used to search for young giant planets and brown dwarfs around ~100
low-mass stars and brown dwarfs in the nearby cluster IC 348. The
observations completed with no reported problems.

1.11 Completed 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 Seven Sets of 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.

1.13 Completed WF/PC-2 9082 (Expansion Distances To The Symbiotic Miras
He 2-104 And He 2-147)

The WF/PC-2 was used to measure the expansion parallax of the
nebulae around the binary symbiotic Miras He 2-104 {the Southern Crab} and
He 2-147 by means of high resolution WFPC2/F658N images to be taken at two
different epochs. Given the large outward velocities of these nebulae
inferred from ground-based spectroscopy, their apparent expansion can be
measured by HST imaging over timescales of only 2-3 years. All
observations completed nominally.

1.14 Completed Two Sets of WF/PC-2/STIS/CCD/MA2 9127 (The UV
interstellar Extinction in Nearby Galaxies: M33)

The WF/PC-2 and the Space Telescope Imaging Spectrograph (CCD and
MA2) were used to investigate further the dust properties that vary in
different environments and from galaxy to galaxy. The proposers had
previously used HST to determine the UV extinction curve in M31. That
result, together with other studies of the Magellanic Clouds and Milky Way,
suggested that the dust particles vary and the proposers plan to enlarge
the sample by studying the UV extinction properties of dust in M33,
sampling different galactocentric distances and levels of star formation
activity. There were no reported problems.

1.15 Completed WF/PC-2 9155 (The Cepheid Distance to NGC 1637: A Direct
Comparison with the EPM Distance to SN 1999em)

The WF/PC-2 was used to directly compare distances estimated by two
primary extragalactic distance indicators. T he appearance of supernova
1999em, a bright, extremely well- observed type II plateau event in the
nearby SBc galaxy NGC 1637 offers the best chance to test the consistency
of the Expanding Photosphere Method {EPM} of supernova distance
determination with that derived from Cepheid variable stars. Although EPM
distances have been measured to 18 type II supernovae out to 180 Mpc and
used to determine Hubble’s constant independent of the Cepheid distance,
there have never been any measurements of Cepheids in a galaxy that has
hosted a normal type II-P supernova, the classic variety of core-collapse
event to which EPM-derived distances are most robust. The proposal
completed nominally.

1.16 Completed WF/PC-2 9042 (An Archive To Detect The Progenitors Of
Massive, Core-Collapse Supernovae)

The WF/PC-2 was used to search for supernovae which have massive
star progenitors. The already extensive HST archive and high-resolution
ground-based images of galaxies within ~20 Mpc enables us to resolve and
quantify their individual bright stellar content. As massive, evolved
stars are the most luminous single objects in a galaxy, the progenitors of
core-collapse supernovae should be directly detectable on pre-explosion
images. One Type II progenitor has been observed this year, and the
investigators have proposed a short, companion WFPC2 proposal to confirm
this candidate and identify a second. The observations completed nominally.

1.17 Completed WF/PC-2 9124 (Mid-UV SNAPSHOT Survey of Nearby
Irregulars: Galaxy Structure and Evolution Benchmark)

The WF/PC-2 was used to investigate the relation between star
formation and the global physical characteristics of galaxies to interpret
the morphologies of distant galaxies in terms of their evolutionary
status. Distant galaxies are primarily observed in their rest frame
mid-ultraviolet. They resemble nearby late-type galaxies, but are they
really physically similar classes of objects? It is proposed to address
this question through a SNAPSHOT survey in the 2 mid-UV filter F300W of 98
nearby late-type, irregular and peculiar galaxies. No problems were reported.

1.18 Completed Two Sets of STIS/CCD 8617 (Ultraviolet Spectroscopy of
Hot Horizontal-Branch Stars in the Globular Cluster M13)

The Space telescope Imaging Spectrograph (CCD) was used to observe
blue horizontal-branch {BHB} stars in the metal-poor globular cluster NGC
6205 that has recently been found to exhibit remarkable metallicity
enhancements and helium depletions relative to the canonical cluster
composition. These abundance anomalies are most likely due to diffusion
processes — radiative levitation of the metals, and gravitational settling
of helium — in the stable radiative atmospheres of these hot stars. With
available ground-based facilities, we have observed stars in M13 as hot as
19000 K, but beyond this point we are constrained by low V- and B-band flux
and an insufficient number of visible-wavelength spectral lines. There
were no reported problems.

1.19 Completed STIS/CCD/MA1 8615 (Ultraviolet Spectroscopy of R Coronae
Borealis Stars — Broad Lines from an Accretion Disc?)

The Space Telescope Imaging Spectrograph (CCD and MA1) was used to
obtain spectra of three R Coronae Borealis {RCB} stars that will provide
novel data on hot gas near these stars.
RCBs are hydrogen-deficient and fade at unpredictable times as a carbon
soot cloud obscures the star. Optical spectra taken when a star has faded
reveal an emission line spectrum containing sharp and broad lines. The
latter are of much higher excitation than the former. For RCB, it has been
suggested that the broad lines arise from an accretion disk around a
compact secondary. These optical lines are visible only during the
infrequent extreme fadings of a RCB. The observations completed as planned.

1.20 Completed STIS/CCD 8846 (Imaging Flats C9)

The Space Telescope Imaging Spectrograph (CCD) was used to
investigate flat-field stability over a monthly period. The proposal
completed nominally.

1.21 Completed WF/PC-2 8191 (The Faintest Radio Galaxies: Interacting
Starbursts at z<1)

Deep WF/PC-2 imaging of the ultra-deep VLA fields of LYNX-16V2 was
performed. There were no reported problems.

2.0 FLIGHT OPERATIONS SUMMARY:

2.1 Guide Star Acquisitions:

Scheduled Acquisitions: 24

Successful: 24

Per HSTAR 8355, the acquisition at 272/191026Z defaulted to fine
lock backup on FGS-3 only when errors arose for FGS-2. The proposals
described in 1.3, 1.7 and 1.9 may have been affected.

Scheduled Re-acquisitions: 22

Successful: 22

2.2 FHST Updates:

Scheduled: 46

Successful: 45

As documented in HSTAR 8356, the roll delay update at 272/013035Z
failed due to tracker #3.

2.3 Operations Notes:

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

The engineering status buffer limits were adjusted three times per
ROP DF-18A.

A TTR was written when STGT began its support at 272/1455Z in the
shadow mode. This resulted in a one-minute, 55-second loss of recoverable
engineering data.

Autonomous SSR engineering record was commanded at 273/1423Z and at
273/1544Z as directed by ROP SR-8A.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

Continuation of normal science observations and calibrations.

SpaceRef staff editor.