HUBBLE SPACE TELESCOPE DAILY REPORT #2907 PERIOD COVERED: 0000Z (UTC) 07/03/01 - 0000Z (UTC) 07/05/01 Daily Status Report as of 186/0000Z 1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED: 1.1 Completed WF/PC-2 9257 (Cycle 10 Super-PSF) The WF/PC-2 was used to obtain deep images of the WFPC2 Point Spread Function (PSF) in several broadband filters in order to investigate the 2-dimensional structure in the PSF wings and characterize the change in structure with varying focus and target color. There were no reported problems. 1.2 Completed Seven Sets of WF/PC-2 8828 (Cycle 9 Supplemental Darks pt3/3) The WF/PC-2 was used to obtain three dark frames every day to provide data for monitoring and characterizing the evolution of hot pixels. The proposal completed with no reported problems. 1.3 Completed Two Sets of WF/PC-2 9162 (Local Galaxy Flows and the Local Mass Density) The WF/PC-2 was used to investigate dark matter which is the main constituent of the universe. It is not know how much there is, how it is distributed, or its composition. Galaxies contain dark matter that extends many tens of kiloparsecs from their centers, but we do not know the limits. The distribution of total mass in the universe can be determined by modelling the orbits galaxies have followed. The proposal completed with no reported problems. 1.4 Completed Seventeen Sets of WF/PC-2 9042 (An Archive To Detect The Progenitors Of Massive, Core-Collapse Supernovae) The WF/PC-s was used to search for supernovae which have massive star progenitors. The already extensive HST archive and high-resolution ground-based images of galaxies within ~20 Mpc enables us to resolve and quantify their individual bright stellar content. As massive, evolved stars are the most luminous single objects in a galaxy, the progenitors of core-collapse supernovae should be directly detectable on pre-explosion images. One Type II progenitor has been observed this year, and the investigators have proposed a short, companion WFPC2 proposal to confirm this candidate and identify a second. The observations completed nominally. 1.5 Completed Six Sets of WF/PC-2 8815 (Cycle 9 Earth Flats) The WF/PC-2 was used to monitor flatfield stability. This proposal obtains sequences of Earth streak flats to construct high quality flat fields for the WF/PC-2 filter set. These flat fields will allow mapping of the OTA illumination pattern and will be used in conjunction with previous internal and external flats to generate new pipeline superflats. The proposal completed nominally. 1.6 Completed WF/PC-2 8935 (Cycle 10 Standard Darks) The WF/PC-2 was used to obtain 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. The proposal completed with no reported problems. 1.7 Completed WF/PC-2 8720 (Masses and Multiplicity of Nearby Free- floating Methane and L Dwarfs) The WF/PC-2 was used to observe 50 very-low-mass objects in the solar neighborhood with spectral types of L0 and later {including several dwarfs with Methane absorption bands in their atmospheres}. These objects will be observed in two filter bands with the aim to identify close companions, measure their colors, and to obtain first epoch data of the newly discovered binaries. The observations completed nominally. 1.8 Completed Three Sets of FGS/1 9034 (The Masses and Luminosities of Population II Stars) Fine Guiidance Sensor #1 was used to observe the mass-luminosity relation {MLR} of Population II stars of which very little is currently known. With the advent of the Hipparcos Catalogue, improved distances to many spectroscopic binaries known to be Pop II systems are now available. After surveying the literature and making reasonable estimates of the secondary masses, we find 13 systems whose minimum separation should be larger than the resolution limit of FGS #1. The observations completed nominally. 1.9 Completed Four Sets of WF/PC-2 9244 (POMS Test Proposal: WFII Parallel Archive Proposal Continuation) The WF/PC-2 was used to perform a generic target version of the Archival Pure Parallel program. The program will be used to take parallel images of random areas of the sky, following the recommendations of the Parallels Working Group. The observations completed with no anomalous activity. 1.10 Completed WF/PC-2 8682 (A Snapshot Study of 0bservational Cosmology) The WF/PC-2 was used to examine the observational constraints on the cosmic star formation history that is currently among the most active fields in observational cosmology. The most widely used tracer of the co-moving volume-averaged star formation rate {SFR} is the UV luminosity density, which early results found to peak at z~1- 2. The apparent identification of the primary epoch of metal production and star formation in the Universe led to intense theoretical and observational interest. Nevertheless, and remarkably for such a fundamental observation, little is known about the history of star formation in the Universe beyond its global average. There were no reported anomalies. 1.11 Completed Five Sets of WF/PC-2 9124 (Mid-UV SNAPSHOT Survey of Nearby Irregulars: Galaxy Structure and Evolution Benchmark) The WF/PC-2 was used to investigate the relation between star formation and the global physical characteristics of galaxies to interpret the morphologies of distant galaxies in terms of their evolutionary status. Distant galaxies are primarily observed in their rest frame mid-ultraviolet. They resemble nearby late-type galaxies, but are they really physically similar classes of objects? It is proposed to address this question through a SNAPSHOT survey in the 2 mid-UV filter F300W of 98 nearby late-type, irregular and peculiar galaxies. No problems were reported. 1.12 Completed WF/PC-2 8632 (A UV Atlas of Nearby Galaxies) The WF/PC-2 was used to perform a snapshot survey of local galaxies at UV wavelengths with the F300W filter. The aim of the project is to build a reference UV Atlas of normal galaxies, whose optical images are well known, with the highest possible degree of information, covering all the morphological types and luminosity classes. The proposal completed normally. 1.13 .26 Completed WF/PC-2 8719 (A Continuation Of A Snapshot Survey Of X- Ray Selected Central Cluster Galaxies) The WF/PC-2 was used to perform snapshot images of a representative subset of the central cluster galaxies from an X-ray selected cluster sample that would provide important constraints on the formation and evolution of dust in cluster cores that cannot be obtained from ground-based observations. The observations completed as planned. 1.14 Completed FGS-1 8783 (Orbits of Pre-Main Sequence Binaries) FGS-1 was used to dynamically measure the masses of low mass pre-main sequence stars. This is important because there are still no low mass young stars with reliably known masses. In cycle 5 we began to map the orbits of young multiple star systems in Taurus using FGS3. The proposal completed with no reported problems. 2.0 FLIGHT OPERATIONS SUMMARY: 2.1 Guide Star Acquisitions: Scheduled Acquisitions: 32 Successful: 32 Scheduled Re-acquisitions: 1 Successful: 1 2.2 FHST Updates: Scheduled: 64 Successful: 64 2.3 Operations Notes: The Space Telescope Imaging Spectrograph (STIS) Side 2 activation began at 184/152337Z. The Side 2 Operate relay was commanded at 184/152955Z. Subsequently, a STIS EEPROM, an EDAC and CS buffer memory dumps were performed. Flight software (FSW) personnel found no miscompares. The Flight Operation Team then began uplinking the FSW segment loads at 184/1713Z. This activity, consisting of 257 segments, is expected to continue until late today. Using ROP SR-1A, the SSR EDAC error counter was cleared five times. The 486 engineering status buffer limits were adjusted three times, per ROP DF-18A. 3.0 SIGNIFICANT FORTHCOMING EVENTS: Resumption of STIS science operations next week. Continuation of other normal science observations and calibrations. /CAW