Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.stsci.edu/ftp/observing/status_reports/old_reports_98/hst_status_06_09_98 Дата изменения: Tue Jun 9 18:51:22 1998 Дата индексирования: Sun Dec 23 10:56:19 2007 Кодировка: Поисковые слова: ngc 6520

HUBBLE SPACE TELESCOPE

DAILY REPORT #2140

PERIOD COVERED: 0000Z (UTC) 06/08/98 - 0000Z (UTC) 06/09/98

Daily Status Report as of 160/0000Z

1.0 ACTIVITIES SCHEDULED AND ACCOMPLISHED:

1.1 Completed NIC/3 7919 (NICMOS Camera 3 Campaign Snapshots)

The Near Infrared Camera (Camera Three) was used to make images of
galaxy NGC-2942 as part of the NICMOS Camera 3 campaign snapshots. The
proposal is to obtain wide field snapshot images of nearby galaxies in
Paschen Alpha which is inaccessible from the ground. The observations were
executed as planned, and no anomalies were reported.

1.2 Completed STIS/CCD 7926 (CCD Dark and Bias Monitor -- Continued)

The Space Telescope Imaging Spectrograph (CCD) was used to make
several dark and bias calibration observations. This is to measure CCD
dark current and bias rates for the two supported amplifier settings {gain
= 1 and gain = 4} in order to gather data for making superdarks and
superbiases. These observations will also track the growth of hot pixels
on the CCD in general and within the various target acquisition apertures
specifically. The observations were executed as scheduled, and no
anomalies were noted.

1.3 Completed Five Sets of WF/PC-2 7620 (WF/PC-2 Cycle 7 Standard Darks)

The WF/PC-2 was used to make a series of Cycle 7 standard dark
calibration images. This dark calibration program obtains 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. During the final iteration of this proposal, as documented in
HSTAR 6519, there were losses of lock that affected one observation (see
2.1 below). Otherwise, the observations were executed as scheduled, and no
anomalies were noted.

1.4 Completed NIC/1/2/3 7872 (A Morphological Census of z > 1 Cluster
Galaxies in the Optical Rest-Frame)

The Near Infrared Camera (Cameras One, Two and Three) was used to
make observations of the galactic cluster containing 3C210. Our existing
WF/PC-2 imaging of this cluster has let us study the rest-frame ultraviolet
light from these galaxies. The proposed NICMOS imaging will allow us to
morphologically classify the cluster galaxies at rest-frame optical
wavelengths and to place them into the context of the Hubble Sequence. The
observations were executed as scheduled, and no anomalies were noted.

1.5 Completed Five Sets of STIS/CCD 7908 (POMS Test Proposal: STIS
Non-Scripted Parallel Proposal)

The Space Telescope Imaging Spectrograph (CCD) was used to make
calibration observations as part of the POMS Test Proposal. This was a
STIS non-scripted parallel proposal. During the final iteration of this
proposal, as documented in HSTAR 6521, there was one loss of lock affecting
one observation. Otherwise, The observations were completed as planned,
and no problems were reported.

1.6 Completed STIS/CCD 8051 (STIS Out-of-Focus PSF)

The Space Telescope Imaging Spectrograph (CCD) was used to make
observations of standard source GRW+70D582 in order to study the
out-of-focus point spread function. As described in HSTAR 6517 and the
previous daily report, the guide star re-acquisition for this proposal
failed, affecting two observations. Otherwise, the observations were
completed as scheduled, and no further anomalies were reported.

1.7 Completed WF/PC-2 8049 (Long WF/PC-2 Decontaminations during 2nd
NIC/3 Campaign)

The WF/PC-2 was used to make long decontamination procedures as part
of the second NIC/3 campaign. Each decon is followed by five 30-minute
darks. During this time, no external science WF/PC-2 observations were
executed. The decontaminations were executed as scheduled, and no
anomalies were noted.

1.8 Completed Two Sets of NIC/1/2/3 7871 (The Properties of High
Redshift Galaxies : A Near-Infrared Redshift Survey)

The Near Infrared Camera (Cameras One, Two and Three) was used to
make infrared galactic survey observations of high redshifted galaxies in s
sky field designated as Field-1417. A comparison between the population of
galaxies in the low {z<1} and high {z>2} redshift universe has shown that
the peak era of star forming activity in the universe occurs in the
redshift interval 1 the first iteration of this proposal, there were multiple losses of lock
that affected two observations. HSTAR 6518 was written. Then, in the
second iteration, there were additional losses of lock described in HSTARs
6519 and 6920 affecting four observations (see 2.1 below). Otherwise, the
observations were executed as scheduled, and no further anomalies were
noted.

1.9 Completed NIC/1 7821 (SINS: The Supernova Intensive Study - Cycle
7+: Scarlet SINS)

The Near Infrared Camera (Camera One) was used to make observations
of the super nova LMC-SN1987 which is located in the Large Magellanic
Cloud. Supernovae create the chemical history of the Universe, energize
the interstellar gas, and stand at the center of efforts to understand the
extragalactic distance scale. As documented in HSTAR 6521, there was one
loss of lock affecting one observation. Otherwise, the observations were
completed as scheduled, and no further problems were noted.

1.10 Completed STIS/CCD 7912 (STIS Parallel Archive Proposal - Nearby
Galaxies - Imaging and Spectroscopy)

The Space Telescope Imaging Spectrograph (CCD) was used to make
parallel observations of nearby galaxies. This survey will be useful to
study the star formation histories, chemical evolution, and distances to
these galaxies. These data will be placed immediately into the Hubble Data
Archive. As documented in HSTAR 6521, there was one loss of lock affecting
one observation. Otherwise, The observations were completed as scheduled,
and no problems were reported.

2.0 FLIGHT OPERATIONS SUMMARY:

2.1 Guide Star Acquisitions:

Scheduled Acquisitions : 5
Successful : 5
Scheduled Reacquisitions : 11
Successful : 11

HSTAR 6519 documents losses of lock at 159/122050Z, at 159/124256Z,
and at 159/124657Z, all during profiled (T3) slews. Proposals described
above in 1.3 (WF/PC-2) and 1.8 (NICMOS) were affected.

HSTAR 6520 documents losses of lock at 159/141522Z and at
159/141921Z, each during profiled (T3) slews. The proposal described in
1.8 (NICMOS) was affected.

HSTAR 6521 documents three occurrences of loss of lock, all during
profiled (T3) slews: at 159/225930Z affecting proposals described in 1.5
(WF/PC-2), 1.9 (NICMOS), and 1.10 (STIS); at 160/001819Z and at 160/003614Z
affecting STIS proposal 7926 (CCD Dark and Bias Monitor - described in
tomorrow's report); and at 160/0214Z, at 160/0224Z, and at 160/0228Z
affecting STIS proposal 7912 (STIS Parallel Archive Proposal/Nearby
Galaxies/Imaging and Spectroscopy - also described in tomorrow's report).

HSTAR 6522 documents losses of lock at 160/0502Z and at 160/0538Z,
each during profiled (T3) slews. STIS proposal 7908 (POMS Test Proposal:
STIS Non-Scripted Parallel Proposal) and NICMOS proposal 7872 (A
Morphological Census of z > 1 Cluster Galaxies in the Optical Rest-Frame),
both of which occur during the period of tomorrow's report, were affected
by these losses of lock.

2.2 FHST Updates:

Scheduled : 7
Successful : 7

2.3 Operations Notes:

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Over the past two weeks, three HSTARs (6509, 6510, and 6516) have
been written on FHST maps using FHST-1. Analysis reveals that all three
maps were at the same attitude - one in which the FOV was directed in the
vicinity of the galactic plane. This resulted in higher background light
during the maps, making it difficult for the FHST to track any suitable
stars. This analysis has shown nominal performance of the hardware. In
the future, FHST-2 and -3 will be used for all maps and updates at this
attitude.

During the same period, numerous HSTARs have been written over the
past week concerning multiple losses of lock, and failed acquisitions and
re-acquisitions (see HSTARs 6519-6522 described in 2.1 above plus HSTARs
6511, 6512, 6514, 6517, and 6518). All of these HSTARs involve a common
guide star (star ID 0347800400) using FGS-2. Investigation finds this star
to be a binary or double star for FGS-2. This has resulted in failure to
achieve fine lock in some cases, and in marginal lock in other cases where
sometimes small T3 slews occurred which resulted in immediate losses of
lock. FGS 2 performance has been checked, and has been found to be
entirely nominal. In addition, the schedule for the next two weeks has
been checked and there are two more cases of this particular star/FGS-2
combination (at 160/0702Z and at 160/1024Z).
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Using ROP SR-1, the SSR EDAC error counter was cleared four times.

A Slot 1 GENSLEW (162-14A) was performed at 159/2053Z as directed by
an operations request.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

Continuation of normal science observations and calibrations.

/DMH