Status Report

NASA Hubble Space Telescope Daily Report #4735

By SpaceRef Editor
November 16, 2008
Filed under , ,


Continuing to collect World Class Science

PERIOD COVERED: 5am November 10 – 5am November 12, 2008 (DOY 315/1000z-317/1000z)


FGS 11942

Increasing the Accuracy of HST Astrometry with FGS1r

We propose to observe six exoplanetary system host stars and two planetary nebulae central stars with FGS1r. All objects have been previously observed under proposals GO-09233, -09969, -10989, and -11210. These observations will significantly extend the time baseline, permitting improvements in the determination of proper motion. This systematic motion must be removed to get at the perturbation of interest, either due to exoplanetary companions or the orbital motion of the Earth (parallax). In most cases the perturbation orbits will also improve. We improve either companion mass or PN parallax. For one target, GJ 876, theoretical dynamical modelers have proposed an inclination closer to 50 degrees, while FGS3 measurements indicated an inclination closer to 84 degrees. These new data, once combined with our older FGS3 data, will permit an independent remeasurement of the inclination of the outermost companion, and a re-evalution of widely used dynamical algorithms.

WFPC2 11867

HH 30

This is a end-of-life WFPC2 imaging program of the disk and jet of the young star HH 30. HH 30 will be observed on PC1 in filters F555W, F675W, and F814W. Jet emission will be seen in F675W extending to the NNW. F555W and F814W each get one orbit of long exposures, and F675W gets two orbits to see the jet at large distances. The orientation is specified to ensure that the jet is not truncated by the chip edge and to place the nearby star XZ Tau in the far corner of WF2.

WFPC2 11796

WFPC2 Cycle 16 Decontaminations and Associated Observations

This proposal is for the WFPC2 decons. Also included are instrument monitors tied to decons: photometric stability check, focus monitor, pre- and post-decon internals (bias, intflats, kspots, & darks), UV throughput check, VISFLAT sweep, and internal UV flat check.

FGS 11789

An Astrometric Calibration of Population II Distance Indicators

In 2002 HST produced a highly precise parallax for RR Lyrae. That measurement resulted in an absolute magnitude, M(V)= 0.61+/-0.11, a useful result, judged by the over ten refereed citations each year since. It is, however, unsatisfactory to have the direct, parallax-based, distance scale of Population II variables based on a single star. We propose, therefore, to obtain the parallaxes of four additional RR Lyrae stars and two Population II Cepheids, or W Vir stars. The Population II Cepheids lie with the RR Lyrae stars on a common K-band Period-Luminosity relation. Using these parallaxes to inform that relationship, we anticipate a zero-point error of 0.04 magnitude. This result should greatly strengthen confidence in the Population II distance scale and increase our understanding of RR Lyrae star and Pop II Cepheid astrophysics.

FGS 11212

Filling the Period Gap for Massive Binaries

The current census of binaries among the massive O-type stars is seriously incomplete for systems in the period range from years to millennia because the radial velocity variations are too small and the angular separations too close for easy detection. Here we propose to discover binaries in this observational gap through a Faint Guidance Sensor SNAP survey of relatively bright targets listed in the Galactic O Star Catalog. Our primary goal is to determine the binary frequency among those in the cluster/association, field, and runaway groups. The results will help us assess the role of binaries in massive star formation and in the processes that lead to the ejection of massive stars from their natal clusters. The program will also lead to the identification of new, close binaries that will be targets of long term spectroscopic and high angular resolution observations to determine their masses and distances. The results will also be important for the interpretation of the spectra of suspected and newly identified binary and multiple systems.

WFPC2 11130

AGNs with Intermediate-mass Black Holes: Testing the Black Hole-Bulge Paradigm, Part II

The recent progress in the study of central black holes in galactic nuclei has led to a general consensus that supermassive {10^6-10^9 solar mass} black holes are closely connected with the formation and evolutionary history of large galaxies, especially their bulge component. Two outstanding issues, however, remain unresolved. Can central black holes form in the absence of a bulge? And does the mass function of central black holes extend below 10^6 solar masses? Intermediate-mass black holes {<10^6 solar masses}, if they exist, may offer important clues to the nature of the seeds of supermassive black holes. Using the SDSS, our group has successfully uncovered a new population of AGNs with intermediate-mass black holes that reside in low-luminosity galaxies. However, very little is known about the detailed morphologies or structural parameters of the host galaxies themselves, including the crucial question of whether they have bulges or not. Surprisingly, the majority of the targets of our Cycle 14 pilot program have structural properties similar to dwarf elliptical galaxies. The statistics from this initial study, however, are really too sparse to reach definitive conclusions on this important new class of black holes. We wish to extend this study to a larger sample, by using the Snapshot mode to obtain WFPC2 F814W images from a parent sample of 175 AGNs with intermediate- mass black holes selected from our final SDSS search. We are particularly keen to determine whether the hosts contain bulges, and if so, how the fundamental plane properties of the host depend on the mass of their central black holes. We will also investigate the environment of this unique class of AGNs.

WFPC2 11113

Binaries in the Kuiper Belt: Probes of Solar System Formation and Evolution

The discovery of binaries in the Kuiper Belt and related small body populations is powering a revolutionary step forward in the study of this remote region. Three quarters of the known binaries in the Kuiper Belt have been discovered with HST, most by our snapshot surveys. The statistics derived from this work are beginning to yield surprising and unexpected results. We have found a strong concentration of binaries among low-inclination Classicals, a possible size cutoff to binaries among the Centaurs, an apparent preference for nearly equal mass binaries, and a strong increase in the number of binaries at small separations. We propose to continue this successful program in Cycle 16; we expect to discover at least 13 new binary systems, targeted to subgroups where these discoveries can have the greatest impact.


Significant Spacecraft Anomalies: (The following are preliminary reports of potential non-nominal performance that will be investigated.)

HSTARS: (None)


18357-2 – ESM Side Switch & FSW Update 315/22:33z 18357-2 – ESM Side Switch & FSW Update 315/22:33z 18358-0 – ESM Return to Side A @ 316/00:55z


                       SCHEDULED      SUCCESSFUL

FGS GSacq               27                 27
FGS REacq               01                 01
OBAD with Maneuver      58                 58


Flash Report: ESM Side Switch, FSW Update, and Return to Side A

At approximately 315/22:36 UTC, Ops Request 18357 was completed, configuring the ESM to use RIU-B and MCU-B in an effort to further isolate the potential cause of the NCS pressure telemetry disparities noted since DOY 290. Upon powering the PCE on the B-side and receiving valid pressure telemetry, no change in the disparities between the TBA and compressor inlet pressures, and the fill bottle and circulator inlet pressures were observed when being read through the redundant electronics. 8051 FSW version 7.0.0 was then successfully loaded into both the high and low banks of EEPROM on MCU-B.

Following validation of the load integrity, after approximately 1 hour of ingesting B-side telemetry, the ESM was transitioned down and reconfigured back to the original RIU-A/MCU-A configuration. While in Boot, the opportunity was taken to load 8051 FSW version 7.00 in to the remaining high EEPROM bank on the A-side as well. Power was restored to the PCE and the NCS CPL was returned to its Standby mode at approximately 316/00:54 UTC, successfully completing Ops Request 18358. The pressure disparities remain unchanged since returning to the A-side.

SpaceRef staff editor.