Hubble Space Telescope Daily Report #2869 – 10 May 2001

HUBBLE SPACE TELESCOPE

DAILY REPORT #2869

PERIOD COVERED: 0000Z (UTC) 05/09/01 – 0000Z (UTC) 05/10/01

Daily Status Report as of 130/0000Z

1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:

1.1 Completed WF/PC-2 8702 (The Most Elusive Nuclei of LMC Planetary
Nebulae)

The WF/PC-2 was used to carry out a SNAPSHOT survey of the faintest
nuclei of planetary nebulae {PNe} in the LMC. This program will be a
crucial follow-on to a Cycle 8 SNAPSHOT of LMC Pne. In thisa case the plan
is to observe the faintest or most obscured nuclei to determine their
evolutionary state to an accuracy not possible in the Galaxy. These
faintest central stars are predicted to be among the most massive nuclei,
and owing to the typically advanced age of the surrounding nebulae, are the
most sensitive discriminants for validating the post-AGB evolution
timescales predicted by theory. The observations completed with no
reported problems.

1.2 Completed Eleven Sets of STIS/CCD 9248 (Probing the Large Scale
Structure: Cosmic Shear Observations)

The Space Telescope Imaging Spectrograph (CCD) was used to measure
the distortion of light bundles from distant galaxies that probe the
statistical properties of the intervening inhomogeneous {dark} matter
distribution. Its tidal gravitational field distorts the observable image
shapes thereby causing a coherent ellipticity pattern {Cosmic Shear}. As
detailed in 2.1 and HSTAR 8212, the acquisition for the ninth iteration of
this proposal failed, affecting one observation when the take data flag
remained down. Otherwise, the observations completed nominally.

1.3 Completed Four 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.

1.4 Completed Four 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.

1.5 Completed FGS/1 9240 (Astrometric Mass Determination of an
Extrasolar Planet Candidate)

Fine Guidance Sensor-1R was used to perform astrometric
observations that will allow a quick measure of the sky-plane motion of 55
Cancri, a G star with an Msin{i} = 0.9 MJ radial velocity companion with a
14 day period. By using 7 pairs of visits, where each visit within a pair
has the same parallax factor, we will be able to accurately determine the
stars’s proper motion. The reflex motion of the star, due to its orbit
about the star-companion barycenter, will manifest itself as a systematic
residual to the measured proper motion if the companion is sufficiently
massive. There were no reported problems.

1.6 Completed Three 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.

1.7 Completed Three Sets of 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.

1.8 Completed Two 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.

1.9 Completed WF/PC-2 8719 (A Continuation Of A Snapshot Survey Of X-
Ray Selected Central Cluster Galaxies)

The WF/PC-2 was used to perform snapshot images of a representative
subset of the central cluster galaxies from an X-ray selected cluster
sample that would provide important constraints on the formation and
evolution of dust in cluster cores that cannot be obtained from
ground-based observations. The observations completed as planned.

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

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

1.11 Completed STIS/CCD/MA1 8620 (Taking A Glance At The Beating Heart
Of 4 Draconis)

The Space Telescope Imaging Spectograph (CCD and MA1) was used to
observe 4 Dra, which is a unique triple system containing a magnetic
cataclysmic variable {AM Her-type} and an M3 III giant. Even though the
M-giant completely dominates the optical emission of the system, we can
learn much from 4 Dra about the accretion physics in and the evolution of
AM Her stars, because: {a} 4 Dra is the second brightest AM Her star in the
ultraviolet, {b} 4 Dra is one of the very few cataclysmic variables with a
good HIPPARCOS parallax {d~180 pc}, and, in addition, {c} 4 Dra is so far
the only bright CV for which an estimate of the age, ~10^8 yrs could be
derived. We propose an in-depth HST/STIS echelle study of the AM Her star
in 4 Dra. Our scientific goals are twofold. {1} We will derive the
fundamental properties of the accreting magnetic white dwarf, such as its
photospheric temperature, the temperature and the size {lateral extent} of
the accretion-heated pole cap, and the chemical composition of the
accretion-enriched atmosphere. {2} We will use the HST/STIS echelle spectra
for Doppler mapping of the UV line emission. The observations completed
without reported incident.

1.12 Completed STIS/CCD 8611 (Observations of Nearby Type Ia Supernovae)

The Space Telescope Imaging Spectrograph (CCD) was used to obtain
UV spectra of five nearby {0.02 < z < 0.08} SNe Ia in the Hubble Flow. The spectra will be taken at weekly intervals over a range in time starting slightly before maximum light and extending to +30 days. These observations will accomplish the following three goals: {1} calibration of the rest frame UV light curves of SNe Ia and an assessment of their potential use as distance indicators through UV light curve shape analyses. {2} improvement in our understanding of the physics of SNe Ia, metallicity/evolutionary effects and correlations between peak brightness and UV spectral features. {3} calibration of the SNe Ia previously observed by HST at high-redshift. This data is crucial for proper cross-filter k-corrections and calibration of the supernova photometry. The observations completed with no reported anomalous activity.

1.13 Completed WF/PC-2/STIS/CCD 8675 (The Massive Star Content of NGC 6822)

The WF/PC-2 and the Space Telescope Imaging Spectrograph (CCD) were
used to characterize the young, coeval stellar population discovered with
WFPC2 multiband imaging in a NGC6822 star-forming region, with follow-up
spectroscopy of the massive star candidates. The proposal completed with
no reported problems.

1.14 Completed Two Sets of WF/PC-2 8604 (Stellar Populations Across the
Small Magellanic Cloud (SMC): History and Structure)

The WF/PC-2 was used to investigate the structure and evolutionary
history of the SMC by obtaining a series of 50 three-color snapshots of
selected SMC regions. With this polling of SMC field star properties, we
will produce color-magnitude diagrams in the U, V and I bands which will
reach V~23.5 in regions too crowded to be observed accurately from the
ground. As detailed in 2.1 and HSTAR 8212, the acquisition for the second
iteration of this proposal failed, affecting three observations when the
take data flag remained down. Otherwise, the observations completed nominally.

1.15 Completed Two Sets of WF/PC-2 8682 (A Snapshot Study of
0bservational Cosmology)

The WF/PC-2 was used to examine the observational constraints on
the cosmic star formation history that is currently among the most active
fields in observational cosmology. The most widely used tracer of the
co-moving volume-averaged star formation rate {SFR} is the UV luminosity
density, which early results found to peak at z~1- 2. The apparent
identification of the primary epoch of metal production and star formation
in the Universe led to intense theoretical and observational
interest. Nevertheless, and remarkably for such a fundamental observation,
little is known about the history of star formation in the Universe beyond
its global average. There were no reported anomalies.

2.0 FLIGHT OPERATIONS SUMMARY:

2.1 Guide Star Acquisitions:

Scheduled Acquisitions: 13

Successful: 12

Per HSTAR 8212, the acquisition at 129/215514Z failed to RGA
control when the search radius limit was exceeded on FGS-3. The following
acquisition was successful. The proposals described in 1.2 and 1.14 were
affected.

Scheduled Re-acquisitions: 2

Successful: 2

2.2 FHST Updates:

Scheduled: 22

Successful: 22

2.3 Operations Notes:

The SSR EDAC error counter was cleared four times per ROP SR-1A.

The CCS status buffer limits (related to acquisition failure
detailed above) were adjusted at 129/2235Z, using ROP DF-18A.

HSTAR 8214 documents the MTE 3A Mag Bar Volts (GMT3AMBV) flagged
out-of-limits with a value of -15.84 from 130/044213Z until 130/044216Z,
from 130/044301Z until 130/044304Z, from 130/044449Z until 130/044452Z, and
from 130/044458Z until 130/044501Z.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

Continuation of normal science observations and calibrations.