Hubble Space Telescope Daily Report #2929 – 6 Aug 2001

HUBBLE SPACE TELESCOPE

DAILY REPORT #2929

PERIOD COVERED: 0000Z (UTC) 08/03/01 – 0000Z (UTC) 08/06/01

Daily Status Report as of 218/0000Z

1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:

1.1 Completed Eleven Sets of STIS/CCD 8808 (POMS Test Proposal: STIS
Non-Scripted Parallel Proposal Continuation III)

The Space Telescope Imaging Spectrograph (CCD) was used to make
non-scripted, parallel observations as part of a POMS test proposal. The
observations completed with no anomalous activity.

1.2 Completed WF/PC-2 8581 (A Search For Low-Mass Companions To
Ultracool Dwarfs)

The WF/PC-2 was used to search for very low-mass {VLM} companions
to a complete sample of 120 late-M and L dwarfs, drawn mainly from the
2MASS and SDSS surveys. The primary goal is to determine the multiplicity
of M < 0.1 M_odot dwarfs. In particular, we aim to identify binary systems suitable for long-term astrometric monitoring and mass measurement, and systems with cool, sub-1000K companions. The proposal completed with no reported problems.

1.3 Completed Six Sets of STIS/CCD 8864 (CCD Dark Monitor-Part 2)

The Space Telescope Imaging Spectrograph (CCD) was used to monitor
the darks for the CCD. The proposal completed nominally.

1.4 Completed Two Sets of WF/PC-2 8820 (Wavelength Stability of Narrow
Band and Linear Ramp Filters)

The WF/PC-2 was used to verify the mapping of wavelength as a
function of CCD position on linear ramp filters and to check for changes in
central wavelengths of the narrow band filters. The proposal completed
nominally.

1.5 Completed Three Sets of STIS/CCD 8865 (Bias Monitor-Part 2)

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. The proposal completed with no anomalous activity.

1.6 Completed Nine Sets of WF/PC-2 8828 (Cycle 9 Supplemental Darks pt3/3)

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

1.7 Completed WF/PC-2 8599 (A Census of Nuclear Star Clusters in
Late-Type Spiral Galaxies)

The WF/PC-2 was used to conduct an I-band snapshot survey of a
well-defined sample of nearby, face-on spiral galaxies of type Scd or
later. The proposal completed nominally.

1.8 Completed Twenty-one Sets of WF/PC-2 8816 (Cycle 9 UV Earthflats)

The WF/PC-2 was used to obtain sequences of Earth streak flats to
improve the quality of pipeline flat fields for the WFPC2 UV filter set and
in order to monitor flat field stability. There were no reported problems.

1.9 Completed WF/PC-2 8701 (Multiplicity among Very-Low Mass Stars and
Brown Dwarfs in Alpha Persei and the Pleiades)

The WF/PC-2 was used to observe open clusters which provide
excellent hunting grounds for brown dwarf {BD} searches. The AlphaPer and
Pleiades clusters are young, nearby and have low extinction. They are
considered to be the best-suited places to study the Substellar Mass. A
dozen of cool faint AlphaPer and Pleiades members have been confirmed as
“bona-fide” BDs with the lithium test. By comparison with those, about
60 very good cluster BD candidates are currently known. The Pleiades SMF
obtained using the most recent deep large CCD surveys indicates that BDs
are quite numerous but do not make a significant contribution to the total
cluster mass. The observations completed with no reported problems.

1.10 Completed Three Sets of WF/PC-2 9057 (Host Galaxies of Obscured
QSOs Identified by 2MASS)

The WF/PC-2 was used to perform a snapshot survey of red QSOs
discovered in The Two Micron All Sky Survey {2MASS} to investigate the
detailed properties of their host galaxies. This large, possibly dominant,
population of QSOs in the local universe has been previously overlooked
because reddening by {intrinsic} obscuration along our line of sight causes
their colors to be too red for identification by traditional “UV- excess”
techniques. Their near-IR colors are similar to PG- type {UV-excess} QSOs,
but it is far from certain whether they are indeed from the same parent
population or represent a completely new class of QSO. There were no
reported problems.

1.11 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.

1.12 Completed STIS/MA1/MA2 8843 (Cycle 9 MAMA Dark Measurements)

The Space Telescope Imaging Spectrograph (MA1 and MA2) was used to
perform the routine monitoring of the MAMA detector dark noise. The
proposal completed nominally.

1.13 Completed WF/PC-2/STIS/CCD 9267 (Supernova Search)

The WF/PC-2 and the Space Telescope Imaging Spectrograph (CCD) were
used to search for high-redshift supernovae in GO-observed fields, taking
advantage of good first-epoch observations and of the scheduling
opportunities available because STIS is not currently observing. No
anomalous activity was reported.

1.14 Completed WF/PC-2 8815 (Cycle 9 Earth Flats)

The WF/PC-2 was used to monitor flatfield stability. This proposal
obtains sequences of Earth streak flats to construct high quality flat
fields for the WF/PC-2 filter set. These flat fields will allow mapping of
the OTA illumination pattern and will be used in conjunction with previous
internal and external flats to generate new pipeline superflats. The
proposal completed nominally.

1.15 Completed STIS/MA2 8624 (Imaging and Spectroscopy of Dusty
Circumstellar Disks)

The Space Telescope Imaging Spectrograph (MA2) was used to further
understanding of the properties and evolution of dusty disks in the
circumstellar environments of young stars which is a key element in
furthering our concepts of the formation mechanisms of extra-solar
planetary systems. The proposal completed with no reported problems.

1.16 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. The observations completed with no anomalous
activity.

1.17 Completed STIS/CCD 7912 (STIS Parallel Archive Proposal – Nearby
Galaxies – Imaging and Spectroscopy)

The Space Telescope Imaging Spectrograph (CCD) was used to make
parallel observations of nearby galaxies. This survey will be useful to
study the star formation histories, chemical evolution, and distances to
these galaxies. These data will be placed immediately into the Hubble Data
Archive. The observations were completed as scheduled, and no problems
were reported.

1.18 Completed WF/PC-2 9043 (Cepheid Distances to Early-type Galaxies)

The WF/PC-2 was used to continue observations in the HST Key
Project on the Extragalactic Distance Scale and the HST project on the
“Calibration of Nearby Type Ia Supernovae” that have greatly improved our
knowledge of the Hubble Constant by providing a solid zero point for the
Tully- Fisher {TF} relation and Type Ia Supernovae {SNIa}. However, severe
inconsistencies remain for distance estimators to early-type galaxies such
as surface brightness fluctuations {SBF}, the planetary nebula luminosity
function {PNLF}, the fundamental plane {FP}, and the globular cluster
luminosity function {GCLF}. As a result, the distance to the Virgo cluster
core remains uncertain by as much as 20 determination is directly affected
by a lingering 0.1 mag {5 uncertainty in the photometric calibration of the
WFPC2. Resolving these issues is essential not only to firm up the
extragalactic distance scale, but also to understand the mass and velocity
structure of the local universe. SBF in particular is emerging as the
method of choice for mapping local velocity fields to 10, 000 kms because
it offers an order of magnitude less Malmquist bias than TF, and SNIa are
too rare to study large scale flows effectively. This project will tighten
the photometric calibration of the WFPC2, and provide a solid Cepheid
calibration for SBF and PNLF. The observations completed nominally.

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

The WF/PC-s 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.

1.20 Completed STIS/CCD 9110 (A Search for Kuiper Belt Object Satellites)

The Space Telescope Imaging Spectrograph (CCD) was used to
investigate whether the large number of collisions thought to have taken
place in the primordial Kuiper belt suggest that many Kuiper belt objects
{KBOs} could have suffered binary-forming collisions similar to that which
formed the Pluto — Charon binary. Detection of such KBO satellites would
allow measurement of KBO masses, would help to understand the past
collisional environment of the Kuiper belt, and would give a context to the
otherwise unique-seeming formation of the Pluto — Charon binary. The
proposal completed with no reported problems.

1.21 Completed STIS/CCD 9121 (Evolution of the Host Galaxies in Low-
Power AGN)

The Space Telescope Imaging Spectrograph (CCD) was used to study
the evolution of low-power AGN host galaxies to z~1.3, allowing the direct
study of how the formation and life cycles of radio-loud AGN depend on
intrinsic power. There were no reported problems.

1.22 Completed Three Sets of STIS/CCD 9063 (Optical Counterparts of
Isolated Neutron Stars)

The Space Telescope Imaging Spectrograph (CCD) was used to test the
understanding of both quantum chromodynamics {QCD} and quantum
electrodynamics {QED}. Specifically, the measurement of radii of neutron
stars can test QCD at high density. This is being realized through
intensive X-ray observations of bright nearby neutron stars. However, the
natures of these important sources are not clear and to this end a simple
proper motion program is proposed as a means to obtain their ages and
potential association with star-forming regions. One of the sources is RX
J0720.4-3125 which has been argued to be an old magnetar — a highly
magnetized neutron star — and thanks to its high count rate is already a
choice object for X-ray missions. Magnetars, with their extreme magnetic
field strengths, are excellent laboratories for testing out some
expectation of QED. There were no reported problems.

1.23 Completed STIS/CCD/MA1 9053 (The Late Evolution of Low-Mass Stars:
a Deep UV Color-Magnitude Diagram of M32)

The Space Telescope Imaging Spectrograph (CCD and MA1) was used to
construct a deep far-UV color-magnitude diagram of the hot stellar
population in the center of M32 {NGC221}. The previous Cycle 7 near-UV
STIS observations of the M32 core resolved 8000 stars in a single
bandpass. While these observations provided no color information, they
nonetheless showed conclusively that hot horizontal branch {HB} stars exist
in M32. Moreover, the near-UV luminosity function showed a surprising lack
of post-asymptotic giant branch {post-AGB} stars, indicating that they
evolve much more rapidly than expected from canonical theory. Obtaining
color information is the vital next step in extending this analysis. There
were no reported problems.

1.24 Completed 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.

1.25 Completed WF/PC-2 8583 (Imaging Snapshots of Asteroids)

The WF/PC-2 was used to obtain images of the fifty largest main
belt asteroids that have favorable apparitions during cycle 9. The images
will be searched for companion bodies, as well as mineralogical variegation
on the resolved main bodies. There were no reported problems.

1.26 Completed Two Sets of 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.

1.27 Completed Two Sets of STIS/CCD 8840 (Read Noise Monitor)

The Space Telescope Imaging Spectrograph (CCD) was used to measure
the read noise of all the amplifiers on the STIS CCD using pairs of bias
frames. Full frame and binned observations are made in both Gain 1 and
Gain 4, with binning factors of 1 x 1, 1 x 2, 2 x 1 and 2 x 2. All
exposures are internals. The observations completed with no reported problems.

1.28 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.

1.29 Completed WF/PC-2/STIS/CCD 8560 (Large Scale Structure at z ~ 0.9)

The WF/PC-2 and the Space Telescope Imaging Spectrograph (CCD) were
used to obtain deep, broad-band red images of three fields within a
supercluster at z ~ 0.9 in order to study the morphological properties of
galaxies within a high-redshift large scale structure. Because significant
evolution has already been observed in galaxy populations at this redshift,
these observations will provide a crucial link between the global
properties of large scale structure and galaxy-scale physics. No problems
were identified.

1.30 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. The observations completed
nominally.

2.0 FLIGHT OPERATIONS SUMMARY:

2.1 Guide Star Acquisitions:

Scheduled Acquisitions: 21

Successful: 21

Scheduled Re-acquisitions: 22

Successful: 22

2.2 FHST Updates:

Scheduled: 59

Successful: 59

2.3 Operations Notes:

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

The STIS MCE-1 reset at 216/003412Z while the low voltage was on
and while inside an SAA interval. The STIS flight software error counter
was reset 216/003412Z, using ROP NS-12. MAMA-1 was recovered at 216/1348Z
via normal SMA commanding.

A TTR was written when there was a required re-transmit at
216/024549Z during an NSSC-1 uplink.

The 486 engineering status buffer limits were adjusted twice per
ROP DF-18A. Using the same ROP, the engineering status buffer was dumped
and reset at 216/1816Z.

A fine attitude determination was performed at 216/1816Z per ROP PO-8.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

Continuation of normal science observations and calibrations.