Status Report

NASA Hubble Space Telescope Daily Report #4695

By SpaceRef Editor
September 15, 2008
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HUBBLE SPACE TELESCOPE DAILY REPORT #4695

Continuing to collect World Class Science

PERIOD COVERED: 5am September 12 – 5am September 15, 2008 (DOY 256/0900z-259/0900z)

OBSERVATIONS SCHEDULED

WFPC2 11797

Supplemental WFPC2 CYCLE 16 Intflat Linearity Check and Filter Rotation Anomaly Monitor

Supplemental observations to 11029, to cover period from Aug 08 to SM4. 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 11022 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.

Note: These are supplemental observations to cover June to SM4 (oct 8 ’08) + 6 months.

ACS/SBC 11322

BEA UV Contamination Monitor

The observations consist of imaging and spectroscopy with ACS/SBC of the scaled OB association NGC 604 in M33 prior to SM4. Data will be obtained with the F122M, F150LP, F165LP filters and the PR130L prism. The observations will allow any UV contamination to be monitored by comparing these data with identical observations to be obtaining during the BEA phase of SMOV4. Also included are a suite of internal Deuterium lamp flat fields to be acquired shortly before the servicing mission for comparison with exactly the same set to be acquired in SMOV/11398.

NIC1/NIC2/NIC3 11318

NICMOS Cycle 16 Multiaccum Darks

The purpose of this proposal is to monitor the dark current, read noise, and shading profile for all three NICMOS detectors throughout the duration of Cycle 16. This proposal is a slightly modified version of proposal 10380 of cycle 13 and 9993 of cycle12 and is the same as Cycle 15. Covers the period from April 08 to November 08 (inclusive)

WFPC2 11316

HST Cycle 16 & Pre-SM4 Optical Monitor

This is a continuation of the Cycle 15 & pre-SM4 Optical Monitor, 11020. Please see that proposal for a more complete description of the observing strategy. The 6 visits comprising this proposal observe two single standard stars with WFPC2/PC in order to establish overall OTA focal length for the purposes of focus maintenance. The goal of this monitoring before SM4 is to establish a best estimate of the OTA focus entering SMOV.

WFPC2 11218

Snapshot Survey for Planetary Nebulae in Globular Clusters of the Local Group

Planetary nebulae {PNe} in globular clusters {GCs} raise a number of interesting issues related to stellar and galactic evolution. The number of PNe known in Milky Way GCs, 4, is surprisingly low if one assumes that all stars pass through a PN stage. However, it is likely that the remnants of stars now evolving in Galactic GCs leave the AGB so slowly that any ejected nebula dissipates long before the star becomes hot enough to ionize it. Thus there should not be ANY PNe in Milky Way GCs–but there are four! It has been suggested that these PNe are the result of mergers of binary stars within GCs, i.e., that they are descendants of blue stragglers. The frequency of occurrence of PNe in external galaxies poses more questions, because it shows a range of almost an order of magnitude. I propose a Snapshot survey aimed at discovering PNe in the GC systems of Local Group galaxies more distant than the Magellanic Clouds. These clusters, some of which may be much younger than their counterparts in the Milky Way, might contain many more PNe than those of our own galaxy. I will use the standard technique of emission-line and continuum imaging, which easily discloses PNe.

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.

WEPC2 11196

An Ultraviolet Survey of Luminous Infrared Galaxies in the Local Universe

At luminosities above 10^11.4 L_sun, the space density of far-infrared selected galaxies exceeds that of optically selected galaxies. These Luminous Infrared Galaxies {LIRGs} are primarily interacting or merging disk galaxies undergoing starbursts and creating/fueling central AGN. We propose far {ACS/SBC/F140LP} and near {WFPC2/PC/F218W} UV imaging of a sample of 27 galaxies drawn from the complete IRAS Revised Bright Galaxy Sample {RBGS} LIRGs sample and known, from our Cycle 14 B and I-band ACS imaging observations, to have significant numbers of bright {23 < B < 21 mag} star clusters in the central 30 arcsec. The HST UV data will be combined with previously obtained HST, Spitzer, and GALEX images to {i} calculate the ages of the clusters as function of merger stage, {ii} measure the amount of UV light in massive star clusters relative to diffuse regions of star formation, {iii} assess the feasibility of using the UV slope to predict the far-IR luminosity {and thus the star formation rate} both among and within IR-luminous galaxies, and {iv} provide a much needed catalog of rest- frame UV morphologies for comparison with rest-frame UV images of high-z LIRGs and Lyman Break Galaxies. These observations will achieve the resolution required to perform both detailed photometry of compact structures and spatial correlations between UV and redder wavelengths for a physical interpretation our IRX-Beta results. The HST UV data, combined with the HST ACS, Spitzer, Chandra, and GALEX observations of this sample, will result in the most comprehensive study of luminous starburst galaxies to date.

WFPC2 11178

Probing Solar System History with Orbits, Masses, and Colors of Transneptunian Binaries

The recent discovery of numerous transneptunian binaries {TNBs} opens a window into dynamical conditions in the protoplanetary disk where they formed as well as the history of subsequent events which sculpted the outer Solar System and emplaced them onto their present day heliocentric orbits. To date, at least 47 TNBs have been discovered, but only about a dozen have had their mutual orbits and separate colors determined, frustrating their use to investigate numerous important scientific questions. The current shortage of data especially cripples scientific investigations requiring statistical comparisons among the ensemble characteristics. We propose to obtain sufficient astrometry and photometry of 23 TNBs to compute their mutual orbits and system masses and to determine separate primary and secondary colors, roughly tripling the sample for which this information is known, as well as extending it to include systems of two near-equal size bodies. To make the most efficient possible use of HST, we will use a Monte Carlo technique to optimally schedule our observations.

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.

WFPC2 11103

A Snapshot Survey of The Most Massive Clusters of Galaxies

We propose the continuation of our highly successful SNAPshot survey of a sample of 125 very X-ray luminous clusters in the redshift range 0.3-0.7. As demonstrated by the 25 snapshots obtained so far in Cycle14 and Cycle15 these systems frequently exhibit strong gravitational lensing as well as spectacular examples of violent galaxy interactions. The proposed observations will provide important constraints on the cluster mass distributions, the physical nature of galaxy-galaxy and galaxy-gas interactions in cluster cores, and a set of optically bright, lensed galaxies for further 8-10m spectroscopy. All of our primary science goals require only the detection and characterization of high-surface-brightness features and are thus achievable even at the reduced sensitivity of WFPC2. Because of their high redshift and thus compact angular scale our target clusters are less adversely affected by the smaller field of view of WFPC2 than more nearby systems. Acknowledging the broad community interest in this sample we waive our data rights for these observations. Due to a clerical error at STScI our approved Cycle15 SNAP program was barred from execution for 3 months and only 6 observations have been performed to date – reinstating this SNAP at Cycle16 priority is of paramount importance to reach meaningful statistics.

FLIGHT OPERATIONS SUMMARY:

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

HSTARS:

11487 – GSAcq 1,2,2 failed due to Search Radius Exceeded on FGS-2 @ 256/17:35:47z

Received one 486 STB message “a05” Exceeded SRL. Mnemonics QF2STOPF and QF2SRLEX flagged out.

Possible observations affected: ACS Proposal 11322, observation 20 – 21.

11489 – NCC (NICMOS CRYO-COOLER) SAFED DURING RESTART

At 258/17:24:43 NCC safed during OPR#18282-0 (NCS Restart and Cooldown). The NCC safed during step 14, NCS PCE On to Circulator On. Status Buffer Message EXEC 908 P=200 T=21011 was received.

11490 – GSacq(1,2,2) Loss Lock

GSacq(1,2,2) starting at 258/20:52z loss lock at 258/21:31:06z prior to Term EXP at 21:33:00z. WFPC2 Observation #121 for Proposal ID #11130 had just completed science data output (3sec prior to the LOL) at 21:31:03z. There were no other flags.

11491 – GSAcq(2,3,2) failed due to Search Radius Limit Exceed on FGS-3.

GSAcq(2,3,2) scheduled at 259/03:08:20 – 03:16:25 failed to RGA Hold due to Search Radius Limit Exceeded on FGS-3.

Possible Observations effected: Astrometry only, Proposal #11212

COMPLETED OPS REQUEST:

18275-0 – Safe NICMOS

18282-0 – NCS Restart and Cooldown (Post-Circulator Safing)

COMPLETED OPS NOTES: (None)

                            SCHEDULED      SUCCESSFUL
FGS GSacq                     29                27
FGS REacq                     10                10
OBAD with Maneuver            78                78

SIGNIFICANT EVENTS:

Flash Report: NICMOS Safed @ 257/01:12:15z, Per Ops Request 18275-1.

Flash Report: NCS Restart operations unsuccessful

Upon execution of circulator start up commanding (Ops Request 18282), a NSCC-1 Status Buffer Message indicated that the circulator was shut down and the NCC was safed due to exceeding the maximum circulator inverter current limit of 130.08 mA (Device Table 251). NCS Restart operations have been suspended pending further review of the start up signature.

SpaceRef staff editor.