HST Daily Report # 3288

HUBBLE SPACE TELESCOPE

DAILY REPORT # 3288

PERIOD COVERED: DOY 27

OBSERVATIONS SCHEDULED

ACS/WFC 9433

The Size Distribution of Kuiper Belt Bodies

The Kuiper Belt is a population of remnant planetesimals from the formation
of
the Solar System. Since the planetesimals in extrasolar systems are too
faint to
see with present or planned telescopes, the Kuiper Belt is our best chance
to
test models of accretional/collisional evolution against observations.
Current
ground-based observations of Kuiper Belt Objects {KBOs} are consistent with
a
pure power law size distribution N{D}propto D^-q, q~4.3. Current accretion
models predict a break to a shallower slope q=3.5 for objects of diameter
D<~100 km. We will conduct a survey of 6 ACS/WFC fields to detect KBOs with R<28.5, and diameters as small as D~10 km. The number of KBOs at these small sizes, unmeasurable from the ground, will test the existence of the predicted break with 95% confidence---we expect between 12 and 50 detections. A census of small KBOs is also important in confirming the idea that short-period comets are errant KBOs. With HST and ground- based followup, we can determine orbital parameters for the detected KBOs, and search for dynamical populations which may be deficient in D>100 km KBOs and hence not yet detected. In particular, we
will
determine whether the current absence of objects with perihelia beyond 50 AU
is
due to a truncation of the protoplanetary disk at some point in Solar System
history, or just a failure to accrete D>150 km objects.

WFPC2 9592

WFPC2 CYCLE 11 Standard Darks

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. Over an extended period these
data
will also provide a monitor of radiation damage to the CCDs.

WFPC2 9594

WFPC2 CYCLE 11 SUPPLEMENTAL DARKS pt2/3

This dark calibration program obtains 3 dark frames every day to provide
data
for monitoring and characterizing the evolution of hot pixels

WFPC2 9599

WFPC2 Cycle 11 UV Earth Flats

Monitor flat field stability. This proposal obtains sequences of earth
streak
flats to improve the quality of pipeline flat fields for the WFPC2 UV filter
set. These Earth flats will complement the UV earth flat data obtained
during
cycles 8-10.

STIS 9605

CCD Dark Monitor-Part 1

Monitor the darks for the STIS CCD

STIS 9607

CCD Bias Monitor – Part 1

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.

STIS 9615

Cycle 11 MAMA Dark Monitor

This test performs the routine monitoring of the MAMA detector dark noise.
This
proposal will provide the primary means of checking on health of the MAMA
detectors systems through frequent monitoring of the background count rate.
The
purpose is to look for evidence of change in dark indicative of detector
problem
developing.

ACS 9673

CCD Daily Monitor

This program consists of basic tests to monitor, the read noise, the
development
of hot pixels and test for any source of noise in ACS CCD detectors. This
programme will be executed once a day for the entire lifetime of ACS

WFPC2 9676

POMS Test Proposal: WFII parallel archive proposal

This is the generic target version of the WFPC2 Archival Pure Parallel
program.
The program will be used to take parallel images of random areas of the sky,
following the recommendations of the 2002 Parallels Working Group.

STIS 9706

STIS Pure Parallel Imaging Program: Cycle 10

This is the default archival pure parallel program for STIS during cycle 10.

FLIGHT OPERATIONS SUMMARY:

Significant Spacecraft Anomalies: (The following are preliminary reports of
potential non-nominal performance that will be investigated.) None

COMPLETED OPS REQs:
None

OPS NOTES EXECUTED:
None

                        SCHEDULED     SUCCESSFUL    FAILURE TIMES
FGS GSacq             4                        4
FGS REacq             14                      14
FHST Update           1                        1
LOSS of LOCK

SIGNIFICANT EVENTS:

Problem with “B” string “core” data server. String to be recycled Tues
morning.