NASA Hubble Space Telescope Daily Report #3952
HUBBLE SPACE TELESCOPE – Continuing to collect World Class Science
DAILY REPORT # 3952
PERIOD COVERED: UT September 23,24,25, 2005 (DOY 266,267,268)
OBSERVATIONS SCHEDULED
NIC1/NIC2/NIC3 8793
NICMOS Post-SAA calibration – CR Persistence Part 4
A new procedure proposed to alleviate the CR-persistence problem of NICMOS. Dark frames will be obtained immediately upon exiting the SAA contour 23, and every time a NICMOS exposure is scheduled within 50 minutes of coming out of the SAA. The darks will be obtained in parallel in all three NICMOS Cameras. The POST-SAA darks will be non-standard reference files available to users with a USEAFTER date/time mark. The keyword ‘USEAFTER=date/time’ will also be added to the header of each POST-SAA DARK frame. The keyword must be populated with the time, in addition to the date, because HST crosses the SAA ~8 times per day so each POST-SAA DARK will need to have the appropriate time specified, for users to identify the ones they need. Both the raw and processed images will be archived as POST-SAA DARKSs. Generally we expect that all NICMOS science/calibration observations started within 50 minutes of leaving an SAA will need such maps to remove the CR persistence from the science images. Each observation will need its own CRMAP, as different SAA passages leave different imprints on the NICMOS detectors.
S/C 4974
TRTTEST
The Transcient Response Test is for the periodic performance monitoring of the FGS 2R servo A mechanism.
ACS/HRC 10623
HST Optical Snapshot Survey of Intermediate Redshift Ultraluminous Infrared Galaxies
Ultraluminous infrared galaxies {ULIGs} are commonly believed to be a transitory phase in the evolution of disk galaxy mergers into QSOs. However, a recently reported discrepancy between the morphological and structural properties of z < 0.13 ULIGs and z = 0.12-0.25 QSOs with M{V} < -23.5 has cast doubt on their evolutionary connection. We propose an ACS snapshot survey of a sample of 39 ULIGs with z = 0.35-1.0. These galaxies are the best suited for comparison with luminous z=0.12-0.25 QSOs because {1} they are at larger lookback times than local ULIGs, and thus are likely representative of the systems that evolve into lower redshift luminous QSOs, {2} they have luminosities comparable to luminous QSOs and, {3} they are selected in a manner that biases the sample towards harboring imbedded AGN, and thus are the most likely precursors to optical QSOs. High resolution HST ACS images will allow a determination of galaxy morphology and reveal the presence of bright AGN. The 2-D profile of each galaxy will be modeled using GALFIT, with the AGN comprising one component of the fit where applicable to better characterize the underlying galaxy. Fundamental parameters {effective radius and surface brightness, and F814W-band magnitude} of the underlying galaxy will thus be measured and compared with the host galaxies of the luminous QSO sample. This imaging campaign will consume a modest amount of HST time, but will provide for the first time a statistically significant view of ULIGs at look-back times of 30-65% the age of the universe, and sufficient resolution and sensitivity to conduct a meaningful comparison with z=0.12-0.25 QSOs, as well as with local {z < 0.3} IRAS-detected and distant {z > 2} SCUBA-detected ULIGs.
NIC2 10620
Massive Star Formation and the Proper Motions of the OMC-1 Molecular Hydrogen Fingers
The Orion Molecular Cloud OMC-1 is by far the nearest region of massive star formation, and as such provides a laboratory for studying massive star formation with unprecedented detail. Using NICMOS, eight years ago our group discovered unique molecular hydrogen ‘fingers’ emanating from the IRc2 area. We propose new NICMOS imaging of the same region to compare with our earlier results. This will determine spatial motions to ~3 AU/year. Using the two data sets, we will: 1} bound the age range of the features and thus address whether all the molecular hydrogen features were produced in a single event – such as an explosion or a stellar merger – or in multiple events/steady outflow; 2} limit the location of the outflow source{s}, which remain to be identified despite sub-arcsecond imaging at thermal infrared wavelengths; and 3} characterize inhomogeneities on the 100 AU scale. Together these findings will significantly constrain how massive star formation proceeds in OMC-1. NICMOS achieves the highest quality, near-infrared images for diffuse objects in crowded regions. Because of the complexity of the OMC-1 region, and the difficulty in using Adaptive Optics to measure small position shifts for diffuse, low contrast objects, these high precision proper motion measurements require the stable PSF, high Strehl ratio, and low response in the PSF wings which HST/NICMOS uniquely provides.
NIC2 10603
Multiwavelength Imaging of Edge-on Protoplanetary Disks: Quantifying the Growth of Circumstellar Dust
Young, edge-on circumstellar disks are uniquely valuable laboratories for the study of planet formation. In these objects, the central star is occulted from direct view, significant PSF artifacts are absent, and the disk is clearly seen as a central dust lane flanked by faint disk reflected light. The detailed morphology of these nebulae and its variation with wavelength provide crucial information on the disk internal structure and the properties of its constituent dust grains. A key observable is the slope defining the wavelength dependence of the dust scattering opacity, which becomes shallower when grain growth has taken place; multiwavelength resolved disk images are the key dataset enabling such measurements. Recent analyses of three different edge-on disks have revealed a diversity in their dust properties that is indicative of different degrees of dust grain evolution having taken place in each system. This characterization of disk grain growth, when applied comparatively to a larger sample of these objects, would enable the construction of an evolutionary sequence of young disks at successive stages on the road to planet formation. In pursuit of this goal, we have identified a sample of 15 edge-on disks previously discovered by HST or groundbased telescopes, but for which high fidelity, high spatial resolution images do not yet exist in both the optical and near-infrared. We propose broad-band multicolor imaging with NICMOS of all these targets, and ACS imaging of nine of these targets In combination with existing data, the proposed images will form a complete database of high resolution optical/near-IR images for these 15 disk systems. Scattered light modeling will be used to derive the disk structure and dust properties, yielding results that will be of fundamental importance for our understanding of grain properties during protoplanetary disk evolution.
ACS/HRC 10572
Resolving M32’s Main Sequence: A Critical Test for Stellar Population Studies
We propose to observe the M32 main-sequence turnoff {MSTO} with deep ACS/HRC B and V images. Only the superior resolution and blue sensitivity of ACS/HRC make this possible. M32 is the only elliptical galaxy close enough to allow direct observation of its MSTO – it is a vital laboratory for deciphering the stellar populations of all other elliptical galaxies, which can only be studied by the spectra of their integrated light, given their greater distances. Major questions about M32’s star formation history remain unanswered. Spectral studies suggest that M32 underwent a recent burst of star formation 3 to 8 billion years ago; observation of the M32 MSTO will confirm this directly. In the process, ACS will easily resolve more luminous components: hot blue stars, luminous, intermediate-age red clump and AGB stars, and any extended blue horizontal branch. These detailed CMDs will provide a direct comparison with population synthesis models for M32, providing a bridge to studies of the integrated light of more distant elliptical galaxies, a crucial ingredient for understanding their star formation histories. As M32 is projected against the edge of the M31 disk, an essential part of our proposal includes deep observation of an M31 disk field to allow the M32 photometry to be background corrected. These observations will reveal the star formation history of M31’s outer disk and are thus of interest in their own right.
ACS/WFC/WFPC2 10558
Archaeology of Fossil Galaxy Groups
Fossil groups are concentrations of dark matter with masses and x-ray luminosities comparable to those of an entire group of galaxies, but whose light is dominated by a single, isolated, large elliptical galaxy. The origin of these systems remains a puzzle: they may be the end products of complete merging of galaxies within once normal groups, or they might originate from a very unusual galaxy luminosity function in those regions that inhibits the formation of moderate-sized galaxies. We propose the first study of the globular cluster populations of the dominant elliptical galaxies in fossil galaxy groups, which will provide important new insights into their origin.
ACS/HRC 10556
Neutral Gas at Redshift z=0.5
Damped Lyman-alpha systems {DLAs} are used to track the bulk of the neutral hydrogen gas in the Universe. Prior to HST UV spectroscopy, they could only be studied from the ground at redshifts z>1.65. However, HST has now permitted us to discover 41 DLAs at z<1.65 in our previous surveys. Followup studies of these systems are providing a wealth of information about the evolution of the neutral gas phase component of the Universe. But one problem is that these 41 low-redshift systems are spread over a wide range of redshifts spanning nearly 70% of the age of the Universe. Consequently, past surveys for low-redshift DLAs have not been able to offer very good precision in any small redshift regime. Here we propose an ACS-HRC- PR200L spectroscopic survey in the redshift interval z=[0.37, 0.7] which we estimate will permit us to discover another 41 DLAs. This will not only allow us to double the number of low-redshift DLAs, but it will also provide a relatively high-precision regime in the low-redshift Universe that can be used to anchor evolutionary studies. Fortunately DLAs have high absorption equivalent width, so ACS-HRC-PR200L has high-enough resoultion to perform this proposed MgII-selected DLA survey.
ACS/HRC 10525
Characterizing the Near-UV Environment of M Dwarfs: Implications for Extrasolar Planetary Searches and Astrobiology
We propose SNAP observations with the ACS HRC PR200L prism, designed to measure the near ultraviolet emission in a sample of 107 nearby M dwarfs. The sample spans the mass range from 0.1 – 0.6 solar masses {temperature range 2200K – 4000K} where the UV energy distributions vary widely between active and inactive stars. The strength and distribution of this UV emission can have critical consequences for the atmospheres of attendant planets. Our proposed observations will provide desperately needed constraints on models of the habitability zone and the atmospheres of possible terrestrial planets orbiting M dwarf hosts, and will be used to sharpen TPF target selection. In addition, the NUV data will be used in conjunction with existing optical, FUV and X-ray data to constrain a new generation of M dwarf atmospheric models, and to explore unanswered questions regarding the dynamo generation and magnetic heating in these low-mass stars.
NIC2 10510
Morphology of massive early-type galaxies at z>1.2: constraining galaxy formation models
We ask for NICMOS-NIC2 H-band imaging of a sample of 10 massive early-type galaxies spectroscopically identified at 1.2
ACS/HRC 10488
The Most Massive Galaxies in the Universe: Color-Gradients and Texture
We are proposing an HST snapshot survey of 40 objects with velocity dispersion larger than 350 km/s, selected from the Sloan Digital Sky Survey and confirmed to be single massive galaxies by the ACS-HRC i-band imaging obtained during Cycle 13. This sample of the most massive galaxies in the Universe is interesting because these objects potentially harbor the most massive black holes, and because their existence places strong constraints on galaxy formation models. These objects are unusual for another reason than their abnormally large velocity dispersions: they appear to be bluer than expected from extrapolation of the color-velocity dispersion relation of normal early-types to these large velocity dispersions. The bluer than expected colors indicate that the formation histories of these objects are likely to be rather different than for normal early-types. This difference is also expected to manifest as abnormal color-gradients. ACS-HRC imaging in one other band {i.e. the g-band} will allow us not simply to analyze color gradients in these objects but also to study their color texture and topology. This study will provide important information about the formation history of galaxies.
ACS/HRC/WFC 10487
A Search for Debris Disks in the Coeval Beta Pictoris Moving Group
Resolved observations of debris disks present us with the opportunity of studying planetary evolution in other solar systems. We propose to search for debris disks in the Beta Pictoris moving group {8-20 Myrs, 10-50 pc away} , which provides a coeval sample of multiple spectral types, and it has already produced two magnificent resolved debris disks: AU Mic and Beta Pic. Such coeval sample will provide us with a snapshop of the crucial time in disk evolution in which the disk makes the transition from optically thick to optically thin, and it will be useful to study the stellar mass dependence of the disk evolution.
ACS/HRC/WFC 10438
The Late Formation of Satellite Galaxies
Tiny isolated HII regions have been discovered up to 30 kpc from the closest galaxy in the NOAO Survey for Ionization in Neutral Gas Galaxies {SINGG}. These halo HII regions can be ionized by only a few OB stars and seem to be most commonly found in interacting systems. They may represent the beginning of the formation of satellite galaxies at low redshift and/or are the source of the numerous intracluster planetary nebula. The halo HII regions are a unique mode of star formation in a low density and low metallicity environment and high resolution HST images are required to identify their underlying stellar populations. Determining the stellar populations of these HII regions will establish whether in-situ star formation is a significant contributor to the stellar content and enrichment of galactic halos and intergalactic space. In particular, ACS/HRC observations are required for their resolution, UV sensitivity, and wide wavelength coverage, allowing young and intermediate age populations to be identified. Parallel ACS/WFC observations will explore the possibility of a further stellar population in the interactive debris. The results of this project have implications on the formation of satellite galaxies, the origin of Galactic halo B stars, IGM ionization and enrichment, and star formation principles.
ACS/HRC/WFC 10389
ACS CCDs daily monitor – Cycle 13 – Part 2
This program consists of a set of basic tests to monitor, the read noise, the development of hot pixels and test for any source of noise in ACS CCD detectors. The files, biases and dark will be used to create reference files for science calibration. This program will be for the entire lifetime of ACS.
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are preliminary reports of potential non-nominal performance that will be investigated.)
HSTARS:
9958 – GSacq(1,3,1) failed, search radius limit exceeded on FGS 1 @ 266/20:59:42z At AOS the map showed errors of V1= 0.71, V2= -1.11, V3= 0.80, RSS= 1.54.
9959 – ACS Target Acquisition Failed due to Guide Star Acq Failure @ 266/21:08:42z ACS target acquisition scheduled at 266/21:07:02 failed due to GSacq failure.
9960 – GSAcq(1,2,1) failed to RGA Control (T2GAttHd) @ 268/12:45:43z The GSAcq(1,2,1) scheduled at 268/12:45:43 – 12:53:47 failed to TGS Submode T2GAttHd. Prior FHST OBAD1 (with maneuver) scheduled at 268/12:28:34 failed to remove error. OBAD Error showed V1= 65046.71, V2=18460.56, V3=15521.12, (RSS)=69374.15 (arcsec). Prior FHST OBAD2 (with maneuver) scheduled at 268/12:41:13 showed vehicle axis errors: V1=707.22, V2=-1949.78, V3=-116.41 (arcsec). 3-axis (RSS) value =2077.34 (arcsec). OBAD using FHST MAP data from 2 FHST was unable to bring attitude error within FGS search radius of 56 arcsec.
9961 – GSACQ(1,2,1) fails, excessive attitude error @ 269/06:32:08z Upon AOS at 07:06:10, HST was in gyro control in M2G mode with no FGS fine lock. GSACQ(1,2,1) at 06:32:08 occurred without telemetry, OBAD error at 06:17:54 had total RSS error of 80374.52 arcseconds, second OBAD at 06:27:09 had total RSS error of 2695.39 arc seconds, greater than guide star search radius. Further information after engineering recorder dump. Observations affected: ACS 17 to 21.
COMPLETED OPS REQUEST:
17545-0 – TRT Trending Test # 9 @ 266/1443z
17552-0 – Genslew for proposal 10487 – slot 10 @ 266/1842z
17551-0 – Genslew for proposal 10487 – slot 11 @ 266/1844z
COMPLETED OPS NOTES: (None)
SCHEDULED SUCCESSFUL FAILURE TIMES FGS Gsacq 20 19 266/20:59:42z (HSTAR # 9958) FGS Reacq 18 16 268/12:45:43z (HSTAR # 9960) 269/06:32:08z (HSTAR # 9961) OBAD with Maneuver 74 72 268/12:31:28z (HSTAR # 9960) 269/06:20:41z (HSTAR # 9961)
SIGNIFICANT EVENTS:
FLASH REPORT: “TRT On-Orbit Test” (summary extract) (Fri, 23 Sep 2005 12:27, from Mike Wenz): “The FGS-2R TRT Trending test was successfully executed on orbit today from 12:57 – 15:07.
FLASH REPORT: “FRR Flash Report: NICMOS CS 5.00 Installation (NV0009)” (summary extract) (Fri, 23 Sep 2005 17:24, from Randy Jay Stevens): “The Flight Readiness Review for the installation of NICMOS CS 5.00 FSW into EEPROM (NV0009) was held on September 23, 2005 in GSFC building 3, S107A. Approval was given to proceed with the installation. Commanding will begin on 269/12:45 (September 26, 8:45 am EST).”
