Hubble Space Telescope Daily Report #2904 29 June 2001

HUBBLE SPACE TELESCOPE

DAILY REPORT #2904

PERIOD COVERED: 0000Z (UTC) 06/28/01 – 0000Z (UTC) 06/29/01

Daily Status Report as of 180/0000Z

1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:

1.1 Completed Two Sets of 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.

1.2 Completed Two Sets of WF/PC-2 8192 (A Snapshot Survey of Probable
Nearby Galaxies)

The WF/PC-2 was used to make a snapshot survey images of a probable
nearby galaxies KK010 and DD06. The census of galaxies in the Local Volume
of space is very incomplete, particularly at the faint end. The
observations were executed as scheduled, and no anomalies were noted.

1.3 Completed Two 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 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.

1.5 Completed WF/PC-2 8601 (A Snapshot Survey of Probable Nearby Galaxies)

The WF/PC-2 was used to continue the very successful snapshot
survey in order to use the high spatial resolution of HST to determine
whether selected galaxies are nearby on the basis of resolution into stars,
and the magnitudes and colors of the brightest stars. There were no
reported problems.

1.6 Completed WF/PC-2 8585 (Cosmological Parameters from Type Ia
Supernovae at High Redshift)

The WF/PC-2 was used to measure the cosmological parameters, Omega,
Lambda, and thus the curvature, Omega_k, using Type Ia supernovae {SNe Ia}
as calibrated standard candles. There were no reported problems.

1.7 Completed 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.

1.8 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
using the HST FGSs. 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 WF/PC-2 8726 (Cometary Knots in Planetary Nebulae)

The WF/PC-2 was used to make second epoch observations of the
Cometary Knots in IC4406 in order to get a better idea of just how these
objects are formed by comparison of their spatial motions with that of the
ambient gas. The observations completed with no reports of problems.

1.10 Completed WF/PC-2 8773 (Expansion Parallax Distances to Planetary
Nebulae)

The WF/PC-2 was used to observe planetary nebulae {PNe} for which
the lack of reliable distances is especially troubling. Acquired by
generalized statistical methods in all but a handful of cases, individual
PNe distances are often uncertain by factors of two or more. The
observations completed nominally.

1.11 Completed WF/PC-2 9045 (The Relationship Between Radio Luminosity
and Radio-Loud AGN Host Galaxy Properties)

The WF/PC-2 was used to determine the relationship between the
properties of the host galaxies of radio-loud AGN and their radio
luminosities. Previous studies in this area with the HST have concentrated
on the 3C sample which shows a tight correlation between luminosity and
redshift, such that evolutionary effects cannot be distinguished from those
depending upon radio luminosity. Our sample of 46 radio galaxies at z ~
0.5 comes from four complete, low-frequency-selected samples of radio
sources with differing flux limits. Thus the total sample spans an
unprecedented three orders of magnitude in radio luminosity at a fixed
redshift interval. The proposal completed with no reported problems.

1.12 Completed WF/PC-2 9086 (Investigating the Formation History of
Spiral Galaxy Halos)

The WF/PC-2 was used to make observations in order to constrain the
origin of spiral galaxy halos by studying stellar populations near the tip
of the red giant branch. This will be the first systematic study of this
population in external galaxies and will quadruple the sample of normal
spiral galaxies for which the halo metallicity distribution function is
measured. This larger sample will permit study of the relationship between
the bulge, disk, and halo components and between halos and globular
systems. Such correlations will in turn provide indications as to whether
the halo, bulge, and globular cluster systems built up nearly
simultaneously in the early universe or were accreted over time through
different kinds of merging events. The proposal completed nominally.

1.13 Completed WF/PC-2 8683 (Imaging Of Brightest Cluster Galaxies: The
High End Of The Black Hole Mass Distribution)

The WF/PC-2 was used to make kinematic black hole detections in
galaxies to decide whether they indicate that the mass correlates with both
optical luminosity and radio power. The observation completed with no
reported problems.

1.14 Completed WF/PC-2 8720 (Masses and Multiplicity of Nearby Free-
floating Methane and L Dwarfs)

The WF/PC-2 was used to observe 50 very-low-mass objects in the
solar neighborhood with spectral types of L0 and later {including several
dwarfs with Methane absorption bands in their atmospheres}. These objects
will be observed in two filter bands with the aim to identify close
companions, measure their colors, and to obtain first epoch data of the
newly discovered binaries. The observations completed nominally.

2.0 FLIGHT OPERATIONS SUMMARY:

2.1 Guide Star Acquisitions:

Scheduled Acquisitions: 11

Successful: 11

Scheduled Re-acquisitions: 4

Successful: 4

2.2 FHST Updates:

Scheduled: 30

Successful: 29

As described in HSTAR 8251, the roll delay update scheduled for
180/003845Z failed due to tracker #3. The following full maneuver update
and the subsequent two full maneuver updates were all successful.

2.3 Operations Notes:

The Space Telescope Imaging Spectrograph (STIS) remains in safe
mode. The VEST Side 2 Operations Acceptance Test successfully completed at
179/2231Z. Flight software personnel verified the load image. The STIS
transition to Operate executed nominally.

Using ROP SR-1A, the SSR EDAC error counter was cleared at 179/2015Z.

The 486 engineering status buffer limits were adjusted at 180/0041Z
per ROP DF-18A.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

Continuation of normal science observations and calibrations.