Status Report

Hubble Space Telescope Daily Report #2833 – 21 Mar 2001

By SpaceRef Editor
March 21, 2001
Filed under ,

HUBBLE SPACE TELESCOPE

DAILY REPORT #2833

PERIOD COVERED: 0000Z (UTC) 03/20/01 – 0000Z (UTC) 03/21/01

Daily Status Report as of 080/0000Z

1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:

1.1 Completed STIS/CCD 8591 (The Smallest Nuclear Black Holes)

The Space Telescope Imaging Spectrograph (CCD) was used to observe
small nuclear black holes which are the last major unexplored part of BH
parameter space, searching for the smallest BHs that HST can possibly
find. The proposal completed with no reported anomalies.

1.2 Completed Eight 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}. The
observations completed nominally.

1.3 Completed Two 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 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.

1.5 Completed WF/PC-2 8719 (A Continuation Of A Snapshot Survey Of X-
Ray Selected Central Cluster Galaxies0

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.

1.6 Completed WF/PC-2 8632 (A UV Atlas of Nearby Galaxies)

The WF/PC-2 was used to perform a snapshot survey of local galaxies
at UV wavelengths with the F300W filter. The aim of the project is to
build a reference UV Atlas of normal galaxies, whose optical images are
well known, with the highest possible degree of information, covering all
the morphological types and luminosity classes. The proposal completed
normally

1.7 Completed Three Sets of WF/PC-2 8827 (Cycle 9 Supplemental Darks pt2/3)

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 nominally.

1.8 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.

1.9 Completed FGS/1 8774 (Calibrating the Mass-Luminosity Relation at
the End of the Main Sequence)

Fine Guidance Sensor #1 was used to calibrate the mass-luminosity
relation {MLR} for stars less massive than 0.2 Msun, with special emphasis
on objects near the stellar/brown dwarf border. Our goals are to determine
Mv values to 0.10 magnitude, masses to 5%, and more than double the number
of objects with masses determined to be less than 0.20 Msun. The proposal
completed with no reported problems.

1.10 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. As described in HSTAR 8129 and 2.1, the
acquisition for the final two iterations of this proposal defaulted to fine
lock backup on one FGS only, possibly affecting the observations in those
iterations. Otherwise, the observations completed with no further
anomalous activity.

1.11 Completed Three Sets of 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.

1.12 Completed STIS/CCD 8170 (Kinematics of the Young Star Clusters and
the Gas in the Antennae Galaxies)

The Space Telescope Imaging Spectrograph (CCD) was used to follow
up on the previous discovery of over 1000 young star clusters in “The
Antennae” {NGC 4038} by obtaining long-slit and slitless spectra of a
representative sample of clusters with STIS. These young clusters have the
luminosities, colors, and radii expected of young globular clusters and
must have formed during the ongoing merger. Because of their proximity and
early stage of merging, the disks of NGC 4038 form an ideal laboratory to
study cluster formation in progress. The observations completed nominally.

1.13 Completed WF/PC-2 8824 (Decontaminations and Associated
Observations Pt. 3/4)

The WF/PC-2 was used for the monthly WFPC2 decons. Also included
are instrument monitors tied to decons: photometric stability check, focus
monitor, pre- and post-decon internals {bias, intflats, kspots, & darks},
UV throughput check, VISFLAT sweep, and internal UV flat check. There were
no reported problems.

1.14 Completed STIS/CCD 8226 (Discerning the Origins of Blue
Stragglers: Masses and Rotation Rates)

The Space Telescope Imaging Spectrograph (CCD) was used to study
the blue stragglers in globular cluster NGC-5272-BS. Conventional wisdom
holds that the masses of Blue Straggler Stars in globular clusters are
significantly larger than the turnoff mass. A wavelength calibration
observation was also taken. As described in HSTAR 8129 and 2.1, the
acquisition for this proposal defaulted to fine lock backup on one FGS
only, possibly affecting the observations in this proposal. Otherwise, the
observations were executed as scheduled, and no further anomalies were noted.

1.15 Completed Two 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. A s described in HSTAR 8129 and
2.1, the acquisition for both iterations of this proposal defaulted to fine
lock backup on one FGS only, possibly affecting all observations in this
proposal. Otherwise, there were no other reported problems.

1.16 Completed Two Sets of WF/PC-2 8698 (Identification of the Galaxy’s
Missing Mass)

The WF/PC-2 was used to observe the nature of dark matter that is
one of the key astrophysical questions of the day. The existence of dark
matter and its dynamical dominance in the outer parts of our Galaxy and
spiral galaxies with flat rotation curves is well established. The MACHO
project has identified ~half of the Milky Way’s dark matter with stellar
objects of ~0.5 M_sun, probably white dwarfs. But the location of the
microlensing in the halo is disputed. Several have detected two candidate
halo white dwarfs of L/L_sun ~ 10^-5 in the Hubble Deep Field with 25 +/- 5
mas/year proper motions. The observations completed with no reported problems.

2.0 FLIGHT OPERATIONS SUMMARY:

2.1 Guide Star Acquisitions:

Scheduled Acquisitions: 7

Successful: 7

Scheduled Re-acquisitions: 8

Successful: 8

Per HSTAR 8129, the acquisition at 079/140558Z defaulted to fine
lock backup on FGS-3 only, as did the following re-acquisitions at
079/153623Z and at 079/171247Z. The proposals described in 1.10, 1.14 and
1.15 may have been affected.

2.2 FHST Updates:

Scheduled: 13

Successful: 13

2.3 Operations Notes:

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

ROP DF-18A was utilized twice to adjust the CCS engineering status
buffer limits.

A TTR was written when there was a generic command drop-out at
080/073039Z during a command load uplink. The re-transmit was successful.

There was a STIS EMC re-try at 080/072519Z. The STIS flight
software error counter was reset at 080/0741Z per ROP NS-12.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

Continuation of normal science observations and calibrations.

SpaceRef staff editor.