HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT      # 4307

PERIOD COVERED: UT February 26, 2007 (DOY 057)

OBSERVATIONS SCHEDULED

ACS/SBC 10862

Comprehensive Auroral Imaging of Jupiter and Saturn during the

International Heliophysical Year

A comprehensive set of observations of the auroral emissions from

Jupiter and Saturn is proposed for the International Heliophysical Year

in 2007, a unique period of especially concentrated measurements of

space physics phenomena throughout the solar system. We propose to

determine the physical relationship of the various auroral processes at

Jupiter and Saturn with conditions in the solar wind at each planet.

This can be accomplished with campaigns of observations, with a sampling

interval not to exceed one day, covering at least one solar rotation.

The solar wind plasma density approaching Jupiter will be measured by

the New Horizons spacecraft, and a separate campaign near opposition in

May 2007 will determine the effect of large-scale variations in the

interplanetary magnetic field {IMF} on the Jovian aurora by

extrapolation from near-Earth solar wind measurements. A similar Saturn

campaign near opposition in Jan. 2007 will combine extrapolated solar

wind data with measurements from a wide range of locations within the

Saturn magnetosphere by Cassini. In the course of making these

observations, it will be possible to fully map the auroral footprints of

Io and the other satellites to determine both the local magnetic field

geometry and the controlling factors in the electromagnetic interaction

of each satellite with the corotating magnetic field and plasma density.

Also in the course of making these observations, the auroral emission

properties will be compared with the properties of the near-IR

ionospheric emissions {from ground-based observations} and non thermal

radio emissions, from ground-based observations for Jupiter?s decametric

radiation and Cassini plasma wave measurements of the Saturn Kilometric

Radiation {SKR}.

WFPC2 11024

WFPC2 CYCLE 15 INTERNAL MONITOR

This calibration proposal is the Cycle 15 routine internal monitor for

WFPC2, to be run weekly to monitor the health of the cameras. A variety

of internal exposures are obtained in order to provide a monitor of the

integrity of the CCD camera electronics in both bays {both gain 7 and

gain 15 -- to test stability of gains and bias levels}, a test for

quantum efficiency in the CCDs, and a monitor for possible buildup of

contaminants on the CCD windows. These also provide raw data for

generating annual super-bias reference files for the calibration

pipeline.

FGS 10989

Astrometric Masses of Extrasolar Planets and Brown Dwarfs

We propose observations with HST/FGS to estimate the astrometric

elements {perturbation orbit semi-major axis and inclination} of

extra-solar planets orbiting six stars. These companions were originally

detected by radial velocity techniques. We have demonstrated that FGS

astrometry of even a short segment of reflex motion, when combined with

extensive radial velocity information, can yield useful inclination

information {McArthur et al. 2004}, allowing us to determine companion

masses. Extrasolar planet masses assist in two ongoing research

frontiers. First, they provide useful boundary conditions for models of

planetary formation and evolution of planetary systems. Second, knowing

that a star in fact has a plantary mass companion, increases the value

of that system to future extrasolar planet observation missions such as

SIM PlanetQuest, TPF, and GAIA.

WFPC2 11023

WFPC2 CYCLE 15 Standard Darks - part 1

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 11029

WFPC2 CYCLE 15 Intflat Linearity Check and Filter Rotation Anomaly

Monitor

Intflat observations will be taken to provide a linearity check: the

linearity test consists of a series of intflats in F555W, in each gain

and each shutter. A combination of intflats, visflats, and earthflats

will be used to check the repeatability of filter wheel motions.

{Intflat sequences tied to decons, visits 1-18 in prop 10363, have been

moved to the cycle 15 decon proposal xxxx for easier scheduling.} Note:

long-exposure WFPC2 intflats must be scheduled during ACS anneals to

prevent stray light from the WFPC2 lamps from contaminating long ACS

external exposures.

WFPC2 11084

Probing the Least Luminous Galaxies in the Local Universe

We propose to obtain deep color-magnitude data of eight new Local Group

galaxies which we recently discovered: Andromeda XI, Andromeda XII, and

Andromeda XIII {satellites of M31}; Canes Venatici I, Canes Venatici II,

Hercules, and Leo IV {satellites of the Milky Way}; and Leo T, a new

"free-floating" Local Group dwarf spheroidal with evidence for recent

star formation and associated H I gas. These represent the least

luminous galaxies known at *any* redshift, and are the only accessible

laboratories for studying this extreme regime of galaxy formation. With

deep WFPC-2 F606W and F814W pointings at their centers, we will

determine whether these objects contain single or multiple age stellar

populations, as well as whether these objects display a range of

metallicities.

WFPC2 11096

Hubble Heritage imaging of Jupiter during the New Horizons encounter HST

Proposal 11096

WFPC2 images of Jupiter in Feb 2007 in support of New Horizons flyby of

Jupiter. This Hubble Heritage DD program is working in concert with the

existing GO programs by John Clarke {10862} and John Spencer {10871}.

FLIGHT OPERATIONS SUMMARY:

Significant Spacecraft Anomalies: (The following are preliminary reports

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

HSTARS:

10716 - GSAcq(2,1,1) Failed to RGA Hold

           GSAcq (2,1,1) scheduled 058/02:27:22 - 02:34:45 failed to RGA Hold (Gyro

           Control) due to mnemonics QF2STOPF and QSTOP flagging.

           OBAD #1 RSS: 1446.83 a-s

           OBAD #2 RSS: 5.34 a-s

           OBAD MAP: not scheduled

COMPLETED OPS REQUEST: (None)

COMPLETED OPS NOTES: (None)

                       SCHEDULED      SUCCESSFUL    

FGS GSacq               08                  07           

FGS REacq               05                  05               

OBAD with Maneuver 26                  26               

SIGNIFICANT EVENTS: (None)