This week on HST


HST Programs: September 28 - October 4, 2009


Program Number Principal Investigator Program Title Links
11108 Esther M. Hu, University of Hawaii Near Infrared Observations of a Sample of z~6.5-6.7 Galaxies Abstract
11208 Tommaso L. Treu, University of California - Santa Barbara The co-evolution of spheroids and black holes in the last six billion years Abstract
11359 Robert W. O'Connell, The University of Virginia Panchromatic WFC3 survey of galaxies at intermediate z: Early Release Science program for Wide Field Camera 3. Abstract
11565 Sebastien Lepine, American Museum of Natural History A search for astrometric companions to very low-mass, Population II stars Abstract
11584 Kristin Chiboucas, University of Hawaii Resolving the Smallest Galaxies with ACS Abstract
11594 John M. O'Meara, Saint Michaels College A WFC3 Grism Survey for Lyman limit absorption at z=2 Abstract
11599 Richard A. Wade, The Pennsylvania State University Distances of Planetary Nebulae from SNAPshots of Resolved Companions Abstract
11603 Jennifer Andrews, Louisiana State University and A & M College A Comprehensive Study of Dust Formation in Type II Supernovae with HST, Spitzer and Gemini Abstract
11606 Dan Batcheldor, Rochester Institute of Technology Dynamical Hypermassive Black Hole Masses Abstract
11613 Roelof S. de Jong, Astrophys. Inst. Potsdam GHOSTS: Stellar Outskirts of Massive Spiral Galaxies Abstract
11629 George G. Pavlov, The Pennsylvania State University Far-UV Phase-resolved Spectroscopy of PSR B0656+14 Abstract
11644 Michael E. Brown, California Institute of Technology A dynamical-compositional survey of the Kuiper belt: a new window into the formation of the outer solar system Abstract
11657 Letizia Stanghellini, National Optical Astronomy Observatories The population of compact planetary nebulae in the Galactic Disk Abstract
11685 Marten H. van Kerkwijk, University of Toronto Supermassive Neutron Stars or Odd binaries: Searching for Companions to Pulsars NGC 6440B and Terzan 5J Abstract
11690 Brian R. Espey, University of Dublin, Trinity College EG And: Providing the Missing Link Required for Modelling Red Giant Mass-loss Abstract
11707 Kailash Sahu, Space Telescope Science Institute Detecting Isolated Black Holes through Astrometric Microlensing Abstract
11713 Howard Bond, Space Telescope Science Institute The Light Echoes around V838 Monocerotis Abstract
11714 Howard E. Bond, Space Telescope Science Institute Snapshot Survey for Planetary Nebulae in Local Group Globular Clusters Abstract
11719 Julianne Dalcanton, University of Washington A Calibration Database for Stellar Models of Asymptotic Giant Branch Stars Abstract
11729 Jon A. Holtzman, New Mexico State University Photometric Metallicity Calibration with WFC3 Specialty Filters Abstract
11737 David M. Meyer, Northwestern University The Distance Dependence of the Interstellar N/O Abundance Ratio: A Gould Belt Influence? Abstract
11788 George Fritz Benedict, University of Texas at Austin The Architecture of Exoplanetary Systems Abstract
11838 Herman L. Marshall, Massachusetts Institute of Technology Completing a Flux-limited Survey for X-ray Emission from Radio Jets Abstract

Selected highlights

GO 11359: Panchromatic WFC3 survey of galaxies at intermediate z: Early Release Science program for Wide Field Camera 3.

HST/ACS images of part of the GOODS field The Great Observatories Origins Deep Survey, is a large-scale program that is designed to probe galaxy formation and evolution at redshifts from z~1 to z~6. GOODS covers two ~150 sq. arcminute fields, one centred on the Hubble Deep Field and the second on the Chandra Deep Field South, and combines deep optical/far-red imaging (F435W, F606W, F775W and F850LP filters) using ACS on HST with deep IRAC (3.6 to 8 micron) and MIPS (25 micron) imaging with Spitzer. Chandra data are also available for the bulk of the field, and NICMOS data H-band (F160W) imaging, coupled with parallel ultraviolet observations using the ACS/SBC, were obtained for a subset of the area in a Cycle 16 contingency program. The present program will build on these observations by using Wide-Field Camera 3 to obtain ultraviolet and near-infrared imaging, and grism spectroscopy, covering ~30% of the GOODS (South) field. The goal is to probe star formation at intermediate redshifts (1 < z < 2).

GO 11788: The Architecture of Exoplanetary Systems

Artist's impression of a young planetary system Immanuel Kant is generally credited with first proposing that the planets in the Solar System coalesced from a flat, rotating disk formed by the Solar Nebula. Direct confirmation of that process only came in the early 1990s, when millimetre-wave interferometers were able to detect molecular gas in Keplerian rotation around a handful of nearby young stars. Since then, there have been numerous other observations, including Hubble's images of proplyds (protoplanetary disks) in the Orion Cluster, and Hubble and Spitzer observations of edge-on disks in other young stars. One of the clear selling points of the Solar Nebula disk model is that it appears to offer a natural path to forming planets with coplanar orbits, matching (most of) our observations of the Solar System. On the other hand, as our knowledge of exoplanetary systems has accumulated over the last decade, it has become clear that dynamical interactions may play a very important role in the evolution of these systems. In particular, disk/planet interactions are generally regarded as responsible for the inward migration of gas giants to form hot Jupiters in <3 day period orbits. Planet-planet interactions could lead to significant changes in orbital inclination. Radial velocity planet searches are uncovering more and more multi-planet systems. This program focuses the high precision of HST's astrometric detectors, the Fine Guidance Sensors, on four of those systems. The aim is to complement the existing radial velocity measurements with sub-milliarcsecond precision astrometry, allowing determination of the true orbital paths - specifically, the relative inclination - of the low-mass objects in these systems.

GO 11713: The Light Echoes around V838 Monocerotis

HST time-lapse imaging of the V838 Mon light echo V838 Mon is the designation of a variable star that appeared within the constellation of Monoceros in early January 2002. Initial observations showed that both the spectrum and light curve resembled that of a nova, and the visual brightness peaked in early February. However, in March the star began to exhibit somewhat unusual behaviour, with a significant increase in the near-infrared brightness, followed by a dip, and then another rise is April before the star returned to its pre-outburst level. Current analyses suggest that this behaviour was prompted by the rapid expansion of the outer atmosphere, producing a shell that cooled as it expanded to give the increased infrared radiation. Shortly after the outburst, imaging showed evidence for extensive light echoes from surrounding gaseous material. HST has been monitoring the appearance of the system, and those observations not only provide a means of mapping the interstellar medium in the vicinity of the star, but have also rendered a direct estimate of the distance, 6.1+/-0.6 kpc. At its brightest, V 838 Mon had an absolute magnitude of MV ~ -9.8, making it one of the brightest stars in the Milky Way.

Past weeks:
page by Neill Reid, updated 23/9/2009