HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

 

DAILY REPORT        # 4537

 

PERIOD COVERED: UT January 30, 2008 (DOY 030)

 

OBSERVATIONS SCHEDULED

 

FGS 11078

 

HST/FGS 1-Gyro On-Orbit Checkout

 

This proposal uses an FGS as an astrometer to observe bright stars

(V<12) in Position mode, with the two other FGSs operating as guiders.

The data obtained by the astrometer will be used to "witness" the

pointing performance of the Observatory in FineLock under 1-gyro

operations. Each visit of this proposal will have a single Pos mode

exposure, the duration of which is to be set by target visibility or by

other tests being conducted in parallel or in sequence with this

proposal. For planning purposes this proposal specifies an exposure time

of 40 minutes, but this can be adjusted as needed.

 

S/C 11345

 

HST/PCS 1-Gyro On-orbit Checkout

 

This proposal contains the part of the on-orbit test that cannot be

satisfied by the science proposals. This includes testing certain M1G,

T1G and F1G capabilities that could potentially compromise any science

data collection, but are needed to validate the robustness of 1-gyro

science mode.

 

WFPC2 11077

 

HST/WFPC2 1-gyro On-orbit Checkout

 

The goal of this program is to verify the performance of the HST under

One Gyro operation.

 

As in previous Two Gyro Testing and Orbital Verification programs the

analysis will be done by characterizating the Point Spread Function

(PSF) of PC1 in the F555W filter.

 

Two Primary issues addressed by this proposal: - PSF structure and

repeatability - Pointing, stability, and offset accuracy.

 

PSF will be characterized as a function of - exposure time - guide star

brightness - sky position

 

For the Pointing we will characterize: - repeatability of small offsets

- stability within visibility period - stability across occultations. as

a function of the guide star brightness

 

The Program requires fifteen orbits: (7 for the main target, 1 for the

secondary target) for two gyro mode, then for 1-gyro mode. The structure

of the visits is identical to the visits executed as part of the program

10458 "ACS and WFPC2 TGSMOV Two-Gyro PSF, Pointing, and Dither Test"

with the only exception of the NICMOS parallel that have been removed.

 

The target selection is based on the visibility in the mid January to

mid February 2008 timeframe. Final target selection will be confirmed

after the analysis of the guide star availability.

 

WFPC2 11497

 

Observations of Mars and 2007 WD5

 

We are proposing to observe 2007 WD5 prior to its possible impact with

Mars. In the event that an impact does occur, we will also observe the

asteroid as it approaches Mars, the impact itself, and the aftermath of

the impact. HST has unique capabilities to observe this potentially very

unusual event.

 

FLIGHT OPERATIONS SUMMARY:

 

Significant Spacecraft Anomalies: (The following are preliminary reports

of potential non-nominal performance that will be investigated.)

 

HSTARS: None

 

COMPLETED OPS REQUEST:

18189-0 - Gyro residual value in TMDIAG

18183-3 - T1G Commanding for OGS OOT

18182-6 - OGS On-Orbit Test

 

COMPLETED OPS NOTES: (None)

 

                          SCHEDULED      SUCCESSFUL 

FGS GSacq                 06                    06                  

FGS REacq                 01                    01                   

OBAD with Maneuver   26                    26

 

SIGNIFICANT EVENTS:

 

Flash Report - Day 2 One Gyro Science (OGS)/Kalman Filter Sun Point

(KFSP) OOT

 

Since the start of the OGS SMS (029/10:00) there have been 12

acquisitions and 42 OBADs. All acquisitions and OBADs have been

successful. We first entered F1G mode at 029/17:08 for the first science

orbit (astrometry observation). The Mars moving target observation began

at 030/10:50. We continued executing Ops Request 18182-6 containing the

script for test execution. Performance appeared nominal with analysis

on-going.