Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.stsci.edu/ftp/observing/status_reports/old_reports_01/hst_status_06_21_01 Дата изменения: Thu Jun 21 14:29:54 2001 Дата индексирования: Sun Dec 23 10:21:04 2007 Кодировка: Поисковые слова: gro j1655-40

HUBBLE SPACE TELESCOPE

DAILY REPORT #2898

PERIOD COVERED: 0000Z (UTC) 06/20/01 - 0000Z (UTC) 06/21/01

Daily Status Report as of 172/0000Z

1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:

1.1 Completed Three 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.

1.2 Completed Two Sets of WF/PC-2 8592 (Pixel Microlensing of M87)

The WF/PC-2 was used to undertake a pixel microlensing study of M87
in order to: 1} probe the lower end of the M87 IMF via star-star lensing,
2} possibly obtain the first evidence of Massive Compact Objects (MACHOs)
in the halo of a galaxy other than our own, and 3} search for intracluster
MACHOs. The proposal completed nominally.

1.3 Completed Two Sets of 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.

1.4 Completed WF/PC-2 9140 (Is GRO J1655-40 a Runaway Black Hole?)

The WF/PC-2 was used to examine the formation of black holes which
is one of the most intriguing problems in astronomy. In the case of
stellar-mass black holes, several theories propose that they are born with
large space velocities. To test this idea we wish to determine the space
velocity of X-ray Nova Scorpii 1994 {GRO J16155-40}, which is one of the
best black hole candidates of stellar mass, and a source of jets with
apparent superluminal motions. This intriguing object is located ~eq
2.5^degrees above the galactic plane and the center of mass of the system
is known to be moving with a large anomalous radial velocity with respect
to the Local Standard of Rest. Since GRO J16155-40 has already been imaged
with the WFPC2 in 1995, one more image with the same instrumental set-up
could allow us to measure its expected proper motion with an accuracy of a
few percent. This observation may provide the first unambiguous evidence
for a black hole formed in the Milky Way that is migrating into
intergalactic space.

1.5 Completed WF/PC-2 8177 (Investigating Type Ia Supernovae and an
Accelerating Universe)

The WF/PC-2 was used to obtain rest frame U and B photometry for
four z~ 0.85 Supernova (SN) Ia. These observations will be coupled to
ground-based rest frame V photometry and spectra. These data, combined
with previous samples, will extend the D_L vs. z diagram for SN Ia to
z~0.85, and allow us to discriminate the redshift dependence of supernova
magnitudes in an accelerating Universe from that expected to result from
systematic effects such as age of the stellar population, chemical
evolution, a drift in the properties of dust, and weak gravitational
lensing. The proposal completed with no reported problems.

1.6 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.

2.0 FLIGHT OPERATIONS SUMMARY:

2.1 Guide Star Acquisitions:
Scheduled Acquisitions: 5
Successful: 5

Scheduled Re-acquisitions: 10
Successful: 10

2.2 FHST Updates:
Scheduled: 10
Successful: 10

2.3 Operations Notes:

The STIS instrument remains in safe mode.

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

Operations personnel participated in GSFC Internal Simulation #9
(EVA-3/PCU) yesterday from 8:00 a.m. until just past midnight.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

Continuation of normal science observations and calibrations.

/CAW