HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science DAILY REPORT       # 4509 PERIOD COVERED: UT December 17, 2007 (DOY 351) OBSERVATIONS SCHEDULED ACS/SBC 11225 The Wavelength Dependence of Accretion Disk Structure We can now routinely measure the size of quasar accretion disks using gravitational microlensing of lensed quasars. The next step to testing accretion disk models is to measure the size of accretion disks as a function of wavelength, particularly at the U ...Continue Reading

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science DAILY REPORT      # 4508 PERIOD COVERED: UT December 14,15,16, 2007 (DOY 348,349,350) OBSERVATIONS SCHEDULED NIC1/NIC2/NIC3 8795 NICMOS Post-SAA calibration - CR Persistence Part 6 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 ...Continue Reading

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science DAILY REPORT       # 4507 PERIOD COVERED: UT December 13, 2007 (DOY 347) OBSERVATIONS SCHEDULED ACS/SBC 11215 New Sightlines for the Study of Intergalactic Helium: Dozens of High-Confidence, UV- Bright Quasars from SDSS/GALEX The reionization of IGM helium is thought to have occurred at redshifts of z=3 to 4. Detailed study of HeII Lyman-alpha absorption toward a handful of QSOs at 2.7<z<3.3 demonstrated the h ...Continue Reading

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science DAILY REPORT      # 4506 PERIOD COVERED: UT December 12, 2007 (DOY 346) OBSERVATIONS SCHEDULED ACS/SBC 11309 Chemical Composition of an Exo-Neptune The recent discovery that the Neptune-like exoplanet GJ 436 b transits its host star has presented us the first chance to observationally study ice giant formation beyond our solar system {Gillon et al. 2007}. Using Directors Discretionary time, we propose to obtain a high-pr ...Continue Reading

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science DAILY REPORT      # 4505 PERIOD COVERED: UT December 11, 2007 (DOY 345) OBSERVATIONS SCHEDULED WFPC2 10877 A Snapshot Survey of the Sites of Recent, Nearby Supernovae During the past few years, robotic {or nearly robotic} searches for supernovae {SNe}, most notably our Lick Observatory Supernova Search {LOSS}, have found hundreds of SNe, many of them in quite nearby galaxies {cz < 4000 km/s}. Most of the objects were ...Continue Reading

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science DAILY REPORT      # 4504 PERIOD COVERED: UT December 10, 2007 (DOY 344) OBSERVATIONS SCHEDULED SIGNIFICANT EVENTS: (None) ACS/SBC WFPC2 11175 UV Imaging to Determine the Location of Residual Star Formation in Galaxies Recently Arrived on the Red Sequence We have identified a sample of low-redshift {z = 0.04 - 0.10} galaxies that are candidates for recent arrival on the red sequence. They have red optical colors indicati ...Continue Reading

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science DAILY REPORT    # 4503 PERIOD COVERED: UT December 7, 8 & 9, 2007 (DOY 341,342,343) OBSERVATIONS SCHEDULED NIC1/NIC2/NIC3 8795 NICMOS Post-SAA calibration - CR Persistence Part 6 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 ...Continue Reading

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science DAILY REPORT      # 4502 PERIOD COVERED: UT December 7, 2007 (DOY 341) OBSERVATIONS SCHEDULED WFPC2 10787 Modes of Star Formation and Nuclear Activity in an Early Universe Laboratory Nearby compact galaxy groups are uniquely suited to exploring the mechanisms of star formation amid repeated and ongoing gravitational encounters, conditions similar to those of the high redshift universe. These dense groups host a variety ...Continue Reading

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science DAILY REPORT      # 4501 PERIOD COVERED: UT December 6, 2007 (DOY 340) OBSERVATIONS SCHEDULED FGS 11211 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 dire ...Continue Reading

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science DAILY REPORT      # 4500 PERIOD COVERED: UT December 5, 2007 (DOY 339) OBSERVATIONS SCHEDULED ACS/SBC 10907 New Sightlines for the Study of Intergalactic Helium: A Dozen High-Confidence, UV-Bright Quasars from SDSS/GALEX The reionization of intergalactic helium is thought to have occurred between redshifts of about 3 and 4. Detailed study of HeII Lyman-alpha absorption toward a handful quasars at 2.7<z<3.3 demonst ...Continue Reading