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Daily 3666
HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science
DAILY REPORT # 3666 PERIOD COVERED: DOY 215 OBSERVATIONS SCHEDULED ACS/HRC 10255 A Never Before Explored Phase Space: Resolving Close White Dwarf / Red Dwarf Binaries We propose an ACS Snapshot imaging survey to resolve a well-defined sample of highly probable white dwarf plus red dwarf close binaries. These candidates were selected from a search for white dwarfs with infrared excess from the 2MASS database. They represent unresolved systems {separations less than approximately 2" in the 2MASS images} and are distributed over the whole sky. Our HST+ACS observations will be sensitive to a separation range {1-20 AU} never before probed by any means. The proposed study will be the first empirical test of binary star parameters in the post-AGB phase, and cannot be accomplished from the ground. By resolving as few as 20 of our ~100 targets with HST, we will be able to characterize the distribution of orbital semi-major axes and secondary star masses. ACS/HRC 9862 ACS detection of sub-stellar companions around Vega, Fomalhaut and beta Pic via parallax & proper motion The first visible light coronagraph on HST provides high contrast ratios near very bright stars. Vega, Fomalhaut and Beta Pictoris have dusty debris disks with structure thought to originate from the presence of yet-undetected, substellar companions. The detection of substellar companions is possible with the ACS HRC coronagraph if observations are made in two epochs. Here we propose to image Vega in two epochs within Cycle 12. We argue that in a few months interval, the sky plane motion of any companions due to parallax and proper motion is large relative to the HRC astrometric uncertainties. Likewise, we propose to obtain a second epoch image of Beta Pic and Fomalhaut within Cycle 12 to complement the single epoch imaging of the GTO program. Because Vega, Fomalhaut and Beta Pictoris are young and nearby, this imaging campaign will be sensitive to brown dwarfs and massive extrasolar giant planets at their predicted locations 40-60 AU projected radius from each star. Either positive or negative results for each system will be used to constrain the physical characteristics of massive objects hypothesized to cause the observed disk asymmetries. ACS/HRC/WFC 10061 CCD Daily Monitor This program consists of basic tests to monitor, the read noise, the development of hot pixels and test for any source of noise in ACS CCD detectors. This programme will be executed once a day for the entire lifetime of ACS. ACS/WFC 10260 The Most Massive Star Clusters: Supermassive Globular Clusters or Dwarf Galaxy Nuclei? Evidence is mounting that the most massive globular clusters, such as Omega Centauri and M31-G1, may be related to the recently discovered "Ultra-Compact Dwarfs" and the dense nuclei of dE, N galaxies. However, no systematic imaging investigation of these supermassive globular clusters -- at the level of Omega Cen and beyond -- has been done, and we do not know what fraction of them might bear the signatures {such as large effective radii or tidal tails} of having originated as dE nuclei. We propose to use the ACS/WFC to obtain deep images of 18 such clusters in NGC 5128 and M31, the two nearest rich globular cluster systems. These globulars are the richest star clusters that can be found in nature, the biggest of them reaching 10^7 Solar masses, and they are likely to represent the results of star formation under the densest and most extreme conditions known. Using the profiles of the clusters including their faint outer envelopes, we will carry out state-of-the-art dynamical modelling of their structures, and look for any clear evidence which would indicate that they are associated with stripped satellites. This study will build on our previous work with STIS and WFPC2 imaging designed to study the 'Fundamental Plane' of globular clusters. When our new work is combined with Archival WFPC2, STIS, and ACS material, we will also be able to construct the definitive mapping of the Fundamental Plane of globular clusters at its uppermost mass range, and confirm whether or not the UCD and dE, N objects occupy a different structural parameter space. NIC/NIC3 10226 The NICMOS Grism Parallel Survey We propose to continue managing the NICMOS pure parallel program. Based on our experience, we are well prepared to make optimal use of the parallel opportunities. The improved sensitivity and efficiency of our observations will substantially increase the number of line-emitting galaxies detected. As our previous work has demonstrated, the most frequently detected line is Halpha at 0.7z1.9, which provides an excellent measure of current star formation rate. We will also detect star-forming and active galaxies in other redshift ranges using other emission lines. The grism observations will produce by far the best available Halpha luminosity functions over the crucial--but poorly observed--redshift range where galaxies appear to have assembled most of their stellar mass. This key process of galaxy evolution needs to be studied with IR data; we found that observations at shorter wavelengths appear to have missed a large fraction of the star-formation in galaxies, due to dust reddening. We will also obtain deep F110W and F160W images, to examine the space densities and morphologies of faint red galaxies. In addition to carrying out the public parallels, we will make the fully reduced and calibrated images and spectra available on-line, with some ground-based data for the deepest parallel fields included. 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. NIC2 9768 Enabling Coronagraphic Polarimetry with NICMOS We propose to enable a new mode on NICMOS that combines the powerful diffracted light rejection of the coronagraph with the diagnostic power of polarimetry. This new capability will open a new regime in high contrast imaging that has not been possible before. We will enable this capability by observing calibration targets with the coronagraph and the NIC2 polarizers in place. The enabled science includes, but is not limited to, detection and imaging of circumstellar debris in polarized light, the polarized emission surrounding bright planetary nebulae, and the extended structure around bright active galaxies. STIS/CCD 10018 CCD Dark Monitor-Part 2 Monitor the darks for the STIS CCD. STIS/CCD 10020 CCD Bias Monitor - Part 2 Monitor the bias in the 1x1, 1x2, 2x1, and 2x2 bin settings at gain=1, and 1x1 at gain = 4, to build up high-S/N superbiases and track the evolution of hot columns. STIS/CCD 10222 The Next Generation Spectral Library We propose to complete our snapshot program to produce a Next Generation Spectral Library of 600 stars for use in modeling the integrated light of galaxies and clusters. This program is using the low dispersion UV and optical gratings of STIS. The library will be roughly equally divided among four metallicities, very low {[Fe/H] -1.5}, low {-1.5 [Fe/H] -0.5}, near-solar {-0.3 [Fe/H] 0.1}, and super-solar {[Fe/H] 0.2}, well-sampling the entire HR-diagram in each bin. Such a library will surpass all extant compilations and have lasting archival value, well into the Next Generation Space Telescope era. Because of the universal utility and community-broad nature of this venture, we waive the entire proprietary period. STIS/CCD 10249 Mass Distributions of z ~ 1 Galaxies: Probing Substructure and Dynamical Evidence for Bulges in Velocity Profiles We propose to use the unique resolving capabilities of STIS to conduct a pilot study of the internal kinematics, structure, and star formation properties of five spiral galaxies at redshifts z ~ 1. Our aim is to determine if these large, rapidly rotating disks have bulges in place at this epoch, and hence can be viewed as direct precursors to their local counterparts. STIS provides a unique opportunity to study the detailed kinematics of distant galaxies, and to probe evolution in the shape of the mass distribution. We have selected targets from a high redshift sample containing 100+ Keck+LRIS major-axis, optical rotation curves for which the [OII]3727A optical emission line has high S/N across the disk. STIS spectroscopy will be combined with existing LRIS spectroscopy and WFPC2, NICMOS and ground-based photometry to derive fundamental structural parameters {rotation velocity profile, stellar mass, mass concentration, disk scale length}, luminosities and star formation rates, and compare them with local counterparts. This will provide a stringent test of current scenarios for the formation of galactic disks and bulges. STIS/CCD/MA1 9736 Integrated Absorption- and Emission-Line Analysis of Nebulae Serious discrepancies have arisen in CNONe abundance determinations for galactic nebulae in the past ten years depending upon which type of emission lines are used in the analysis: forbidden vs. permitted lines. The cause of the discrepancies, which can exceed an order of magnitude for some PNe, has been studied intensively but is still unknown. Emission line abundances cannot be considered reliable until the nature of these contradictory results is understood. We have developed a technique for integrating absorption lines into emission analyses for diffuse nebulae that provides an independent check on the validity of emission-line analyses. It requires high resolution observations of UV resonance absorption produced by the nebular gas in imbedded or background stars together with optical spectra of the nebulae. We propose to obtain UV spectra of four PNe central stars with STIS that will provide data necessary to exploit the new technique of integrated abundance determination that combines both emission and absorption lines. STIS/MA1 10034 Cycle 12 MAMA Dark Monitor This test performs the routine monitoring of the MAMA detector dark noise. This proposal will provide the primary means of checking on health of the MAMA detectors systems through frequent monitoring of the background count rate. The purpose is to look for evidence of change in dark indicative of detector problem developing. WFPC2 10068 WFPC2 CYCLE 12 Standard Darks 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 10071 WFPC2 CYCLE 12 Supplemental Darks Part 3/3 This dark calibration program obtains 3 dark frames every day to provide data for monitoring and characterizing the evolution of hot pixels. WFPC2 10072 WFPC2 CYCLE 12 INTERNAL MONITOR This calibration proposal is the Cycle 12 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 {gain 7 and gain 15}, a test for quantum efficiency in the CCDs, and a monitor for possible buildup of contaminants on the CCD windows. FLIGHT OPERATIONS SUMMARY: Significant Spacecraft Anomalies: (The following are preliminary reports of potential non-nominal performance that will be investigated.) HSTAR 9496: FHST Roll Delay Update (U1,2RD) @ 215/10:02:00Z failed with Error Box indicating "2 FAILED" for mnemonics QEBSTFG0, QEBSTFG1, and QEBSTFG2 @ 215/10:02:49Z. FHST 2 failed to locate the Reference Star (ID 20440003, or eta Indi) of magnitude 4.52 Mv. Under investigation. HSTAR 9499: Upon AOS @ 216/07:41:02Z, a single 486 Status Buffer message "a05" was observed, indicating "FGS coarse track failed, SRLE" during the primary GS acquisition (1,2,2) @ 216/07:25:04Z. Vehicle was in FL on FGS 1 and 2 at AOS, no observations affected. Further analysis after engineering recorder dump scheduled for 216/23:28Z. Upon AOS @ 216/09:06:00Z, a second 486 Status Buffer message "a05" was observed, and vehicle was operating on gyro control only. GS Reacquisition (1,2,2) @ 216/08:57:58Z failed to reacquire GSs. Real-time FHST Map @ 216/09:30Z showed attitude errors of -0.901, 14.808, and 11.332 arcsec, no attitude problem was apparent. Under investigation. COMPLETED OPS REQs: None OPS NOTES EXECUTED: 1251-0 Adjust Recharge Ratio Limits for High Sun DOY 2004/203-215 @ 215/1201z SCHEDULED SUCCESSFUL FAILURE TIMES FGS GSacq 09 09 FGS REacq 05 05 FHST Update 15 14 215/10:02:49z LOSS of LOCK SIGNIFICANT EVENTS: None |
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