Status Report

Hubble Space Telescope Daily Report # #3003 – 23 Nov 2001

By SpaceRef Editor

November 23, 2001

Filed under Hubble Space Telescope, Space Telescope Science Institute, US

HUBBLE SPACE TELESCOPE

DAILY REPORT #3003

PERIOD COVERED: 0000Z (UTC) 11/21/01 – 0000Z (UTC) 11/23/01

Daily Status Report as of 327/0000Z

1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:

1.1 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. No problems occurred.

1.2 Completed Three Sets of WF/PC-2 8942 (Cycle 10 Intflat Sweeps and
Linearity Test)

The WF/PC-2 was used to monitor the pixel-to-pixel flatfield
response and provide a linearity check. These intflat sequences are done
once during the year and the images will provide a backup database in the
event of complete failure of the visflat lamp as well as allow monitoring
of the gain ratios. There were no reported problems.

1.3 Completed STIS/CCD/MA1/MA2 8916 (Spectroscopic Sensitivity Workout:
First-order Modes)

The Space Telescope Imaging Spectrograph (CCD, MA1 and MA2) was
used to measure the basic sensitivity for all supported MAMA and CCD
first-order spectroscopic modes. Sensitivity measurements are done for all
supported tilts of the gratings, at a S/N suitable to any particular
setting, in order to get all measurements done in a reasonable number of
orbits but still get a very accurate sensitivity measurement. There were
no reported problems.

1.4 Completed Five 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.

1.5 Completed Seven 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 FGS/1 9175 (The Best Brown Dwarf Yet?: FGS
Astrometry of the Companion to the Hyades Eclipsing Binary V471 Tau)

Fine Guidance Sensor #1 was used to perform observations of V471
Tau over the next 3 years {2 HST orbits/year} to determine its astrometric
orbit. These HST observations, when combined with Hipparcos astrometry and
the light time orbit, will unambiguously yield the orbital inclination and
the mass of a possible brown dwarf. The identification of a brown dwarf in
V471 Tau will provide the first direct dynamical mass determination of a
brown dwarf with a known age, chemical composition, and distance. As
mentioned in 2.3, at least one observation in the second iteration of this
proposal failed. Otherwise, it is believed that all other observations
completed nominally.

1.7 Completed Four 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.

1.8 Completed Four Sets of STIS/CCD 8910 (Sparse Field CTE
Test-Internal {Cycle 10})

The Space Telescope Imaging Spectrograph (CCD) was used to perform
CTE measurements that are made using the “sparse field test”, along both
the serial and parallel axes. This program needs special commanding to
provide {a} off-center MSM positionings of some slits, and {b} the ability
to read out with any amplifier {A, B, C, or D}. No problems were encountered.

1.9 Completed FGS/1 9168 (The Distances to AM CVn Stars)

Fine Guidance Sensor (FGS) #1 was used to determine the parallaxes
and proper motions of the five brightest of the seven known AM CVn
systems. AM CVn systems are binaries where mass is transferred from a
completely hydrogen-deficient, degenerate mass donor to a white dwarf
primary through a helium accretion disk. A better understanding of these
systems is crucial for a number of reasons: (1) to study the late stages of
binary evolution, (2) to study the effect of chemical composition on the
physics of accretion discs, (3) to estimate their contribution to the
Supernovae Ia rate, and (4) to estimate their contribution to the
gravitational radiation background. All observations completed with no
reported problems.

1.10 Completed WF/PC-2 9129 (Evolution of the Bow Shock in the Guitar
Nebula)

The WF/PC-2 was used to take observations of the Guitar Nebula, a
bow shock produced by the high-velocity pulsar B2224+65. By comparison
with a previous observation in 1994, a new narrow-band H-alpha image will
allow exploitation of the change in pulsar location {~1″}, in order to: {a}
quantify ambient interstellar density variations on scales <=10^-3 pc that perturb the shape of the bowshock near the contact discontinuity {size ~0.2"}; and {b} better model the bowshock to determine the orientation of the pulsar velocity vector. No problems were reported.

1.11 Completed Nine 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.

1.12 Completed Five 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.

1.13 Completed STIS/CCD 9312 (POMS Test Proposal: STIS Non-scripted
Parallel Proposal Continuation IV)

1.14 Completed Two 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. The proposal completed uneventfully.

1.15 Completed Three Sets of STIS/CCD/MA2 9105 (Determination of the
Distances and Masses of 3 Galactic Cepheids)

The Space Telescope Imaging Spectrograph (CCD and MA2) was used to
continue a successful observing strategy which enabled the proposers to
accurately measure angular separations < 10^-2'' with the FOC for binaries with Cepheid primaries and main sequence B or A star secondaries {our accuracy should improve to ~10^-3'' with STIS}. Once measurements are available at two carefully selected phases and these are combined with spectroscopic orbits, the angular information will enable the masses and distances for the binaries to be determined from Newton's laws and Euclidean geometry. The distances determinations amount to bypassing two rungs of the cosmic distance ladder: the moving-cluster distance to the Hyades and main sequence fitting of clusters containing Cepheids. The mass determinations will provide the first direct dynamical mass measurements for Cepheids, providing sorely needed quantitative information on this poorly understood stage of massive star evolution. The proposal completed with no reported problems.

1.16 Completed Three Sets of STIS/MA1/MA2 8920 (Cycle 10 MAMA Dark
Measurements)

The Space Telescope Imaging Spectrograph (MA1 and MA2) was used to
perform the routine monitoring of the MAMA detector dark noise, and is the
primary means of checking on health of the MAMA detectors systems through
frequent monitoring of the background count rate. The proposal completed
with no reported anomalous activity.

1.17 Completed WF/PC-2 9060 (Photometry of a Statistically Significant
Sample of Kuiper Belt Objects)

The WF/PC-2 was used to propel the physical study of KBOs forward
by performing accurate photometry at V, R, and I on a sample of up to 150
KBOs. The sample is made up of objects that will be observed at thermal
infrared wavelengths by SIRTF and will be used with those data to derive
the first accurate diameters and albedos for a large sample of KBOs. The
observations completed nominally.

1.18 Completed STIS/CCD/MA2 9119 (Io’s Prometheus Plume, and the
Composition and Spatial Distribution of Io’s Atmosphere)

The Space Telescope Imaging Spectrograph (CCD and MA2) was used to
obtain the most detailed view yet of Io’s dynamic SO_2 / S_2 atmosphere,
and the first spectroscopic observations of a Prometheus-type plume, to
test models of plume and atmospheric chemistry and dynamics. The proposal
completed a splanned.

1.19 Completed Two Sets of WF/PC-2 9138 (Host Galaxies of
Gravitationally Lensed Quasars)

The WF/PC-2 was used to perform imaging studies of quasar host
galaxies at high redshift that are biased toward detecting luminous
hosts. Gravitational lensing combined with optical and near-IR imaging
enhances their detectivity and has nearly doubled the number of known hosts
at z>1. Lens studies have successfully imaged hosts with lower
luminosities at farther distances beneath a larger fraction of quasars than
imaging of non- lensed quasars. We propose deep WFPC2 follow-up imaging of
five lensed systems in the F555W and F814W filters, which offer unique
opportunities for detailed studies of faint, high-redshift, quasar
hosts. The proposal completed as planned.

1.20 Completed STIS/CCD 8908 (CCD Imaging Flats C10)

The Space Telescope Imaging Spectrograph (CCD) was used to
investigate flat-field stability over a monthly period. The proposal
completed with no reported problems.

2.0 FLIGHT OPERATIONS SUMMARY:

2.1 Guide Star Acquisitions:

Scheduled Acquisitions: 17

Successful: 17

Scheduled Re-acquisitions: 15

Successful: 15

2.2 FHST Updates:

Scheduled: 34

Successful: 32

Per HSTAR 8402, the full maneuver update scheduled at 325/162145Z
failed due to tracker 3. The following acquisition was successful.

The update at 327/081153Z failed.

2.3 Operations Notes: