Status Report

Hubble Space Telescope Daily Report #3049 – 5 Feb 2002

By SpaceRef Editor
February 5, 2002
Filed under , ,



PERIOD COVERED: 0000Z (UTC) 02/04/02 – 0000Z (UTC) 02/05/02

Daily Status Report as of 036/0000Z


1.1 Completed Three Sets of WF/PC-2 8937 (Cycle 9 Supplemental Darks pt2/3)

The WF/PC-2 was used obtain three dark frames every day to provide
data for monitoring and characterizing the evolution of hot pixels. No
problems were encountered.

1.2 Completed Three Sets of STIS/CCD 8906 (Hot Pixel Annealing)

The Space Telescope Imaging Spectrograph (CCD) was used to measure
the effectiveness of the CCD hot pixel annealing process by measuring the
dark current behavior before and after annealing and by searching for any
window contamination effects. In addition, CTE performance is examined by
looking for traps in a low signal level flat. The acquisition failure
detailed in HSTAR 8490 and 2.1 occurred for the third iteration of this
proposal and two observations were lost. There were no other reported
problems in the other iterations.

1.3 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.

1.4 Completed Six Sets of WF/PC-2 8935 (Cycle 10 Standard Darks)

The WF/PC-2 was used to obtain dark frames every week in order to
provide data for the ongoing calibration of the CCD dark current rate, and
to monitor and characterize the evolution of hot pixels. Over an extended
period these data will also provide a monitor of radiation damage to the
CCDs. The proposal completed with no reported problems.

1.5 Completed Eight Sets of WF/PC-2 9318 (POMS Test Proposal: WFII
Parallel Archive Proposal Continuation)

The WF/PC-2 was used to perform the generic target version of the
WFPC2 Archival Pure Parallel program. The program was used to take
parallel images of random areas of the sky, following the recommendations
of the Parallels Working Group. There were no reported problems.

1.6 Completed WF/PC-2 8939 (Cycle 10 Internal Monitor)

The WF/PC-2 was used to calibrate the internal monitor, to be run
weekly to monitor the health of the cameras. No problems were encountered.

1.7 Completed WF/PC-2 9087 (Black Hole X-ray Transients and X-ray
Binaries in M31)

The WF/PC-2 was used to search for M31 for x-ray transients which
had previously been seen as part of the Chandra Guaranteed Time
Observations {GTO} program. The x-ray properties of these transient
sources {spectra, variability} allow us to determine whether the accreting
object is a black hole or a neutron star. It is proposed to determine the
nature of the mass-losing star. Massive stars will show little [<2 mag] change in their UV luminosities during outbursts, while low-mass stars will show large [>5 mag] changes in their UV luminosities. By determining the
nature of the primary {accreting} and secondary stars in these x-ray
transients, we will have the first dataset that will allow the evolution of
black hole and neutron star binaries to be studied in an external
galaxy. The proposal completed nominally.

1.8 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.

1.9 Completed Two Sets of 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
acquisition failure detailed in HSTAR 8490 and 2.1 occurred for the second
iteration of this proposal and four observations were lost. Otherwise. the
other iteration completed nominally.

1.10 Completed WF/PC-2 9101 (Toward Understanding the Bipolar
Geometries of Preplanetary Nebulae with High-Velocity Polar Flows)

The WF/PC-2 was used to image 17 preplanetary nebula for comparison
with high-resolution spectral-line images {being obtained with
VLA/MERLIN/ATCA}, enabling us to understand the fast outflow and how its
hydrodynamical interaction with the AGB wind produces a bipolar nebula. No
problems were reported.

1.11 Completed STIS/CCD/MA1 8571 (Metallicity and D/H Abundance in
Low-Z LyAlpha Absorbers towards PG 1211+143)

The Space Telescope Imaging Spectrograph (CCD and MA1) was used to
continue previous observations along the sightline toward PG 1211+143 that
reveal numerous LyAlpha absorption lines including two very strong LyAlpha
absorbers {cz = 15, 300 and 19, 550 km s^- 1} with associated Si III
absorption. These are the first definite detections of metals in a low-z
LyAlpha forest cloud. Simple photoionization models suggest metallicities
in the range 1–10 sim10^17 cm^-2 in each system. The proposers should be
able to detect deuterium LyAlpha at 10–20 mAngstrom equivalent width,
thereby testing models of D/H astration as a function of IGM metallicity,
an issue of cosmological significance. There were no problems.

1.12 Completed WF/PC-2 8941 (Cycle 10 UV Earthflats)

The WF/PC-2 was used to monitor flat field stability by obtaining
sequences of earth streak flats to improve the quality of pipeline flat
fields for the WFPC2 UV filter set. The proposal had no problems.

1.13 Completed 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.


2.1 Guide Star Acquisitions:

Scheduled Acquisitions: 7

Successful: 6

The acquisition scheduled at 035/192933Z failed to gyro control
when the search radius limit was exceeded on FGS-3. The take data flag
remained down and the proposals described in 1.3 and 1.9 were
affected. HSTAR 8490 was written.

Scheduled Re-acquisitions: 7

Successful: 7

2.2 FHST Updates:

Scheduled: 21

Successful: 21

2.3 Operations Notes:

The engineering status buffer limits were adjusted (HGA torque
limit =7) at 035/1933Z, using ROP DF-18A.

Several CCL quick updates were made at 035.2030Z and the new TCL
BATCAPAJ was executed, all as directed by an operations request.

Per an operations request, the pressure-based battery equation was
updated at 035/2031Z.

The ephemeris table was loaded at 036/0124Z per ROP DF-07A.


Continuation of normal science observations and calibrations.

SpaceRef staff editor.