This week on HST

HST Programs: October 23 - October 29 2017

Program Number Principal Investigator Program Title
14597 Jay Farihi, University College London An Ultraviolet Spectral Legacy of Polluted White Dwarfs
14734 Nitya Kallivayalil, The University of Virginia Milky Way Cosmology: Laying the Foundation for Full 6-D Dynamical Mapping of the Nearby Universe
14765 Ian U. Roederer, University of Michigan The Unexplored Domains of the s-Process
14767 David Kent Sing, University of Exeter The Panchromatic Comparative Exoplanetary Treasury Program
14789 Thomas R. Ayres, University of Colorado at Boulder Procyon: New Candidate for the Dynamo Clinical Trial
14840 Andrea Bellini, Space Telescope Science Institute Schedule Gap Pilot
15115 John David Silverman, University of Tokyo Emergence of the supermassive black hole - galaxy mass relations at z > 1
15133 Peter Erwin, Max-Planck-Institut fur extraterrestrische Physik Solving the Mystery of Galaxy Bulges and Bulge Substructure
15140 Ragnhild Lunnan, Stockholm University Resolving the Connection Between Superluminous Supernovae and Star Formation in Dwarf Galaxies
15145 Adam Riess, The Johns Hopkins University The Hubble Constant to 1%: Physics beyond LambdaCDM
15149 Alex Teachey, Columbia University in the City of New York Validating the Presence of a Moon Orbiting Kepler-1625b
15158 Marc W. Buie, Southwest Research Institute Astrometry of 2014MU69 for New Horizons encounter
15162 Peter Blanchard, Harvard University Constraining the Late-Time Light Curve Behavior of Three Diverse Superluminous Supernovae
15201 Clemence Fontanive, Royal Observatory Edinburgh Looking for the Coldest Atmospheres: a Search for Planetary Mass Companions around T and Y Brown Dwarfs
15215 Vardha N. Bennert, Cal Poly Corporation, Sponsored Programs Department A Local Baseline of the Black Hole Mass - Host Galaxy Scaling Relations for Active Galaxies
15241 Kirsten L. Larson, California Institute of Technology Clumpy Star Formation in Local LIRGS
15242 Lucia Marchetti, Open University SNAPshot observations of the largest sample of lensed candidates in the Equatorial and Southern Sky identified with Herschel
15262 Amy Simon, NASA Goddard Space Flight Center Hubble 2020: Outer Planet Atmospheres Legacy (OPAL) Program
15279 Sean Johnson, Princeton University Unveiling Quasar Fueling through a Public Snapshot Survey of Quasar Host Environments
15307 Michael D. Gladders, University of Chicago Building the SPT-HST Legacy: Imaging Massive Clusters to z=1.5
15318 Kailash C. Sahu, Space Telescope Science Institute Detecting Isolated Black Holes through Astrometric Microlensing
15344 David Jewitt, University of California - Los Angeles Centaurs and Activity Beyond the Water Sublimation Zone
15380 Laurent Lamy, Observatoire de Paris - Section de Meudon Hunting the successive auroral response of Uranus and Neptune to unexpected powerful heliospheric disturbances

Selected highlights

GO 14734: Milky Way Cosmology: Laying the Foundation for Full 6-D Dynamical Mapping of the Nearby Universe

The low-mass dwarf galaxy, Leo II
The Milky Way, M31 and M33 are the three largest galaxies in the Local Group. That system, however, includes more than 25 other members, with the majority being dwarf spheroidal galaxies that are satellites of either M31 or the Milky Way. Those galaxies have old, evolved stellar populations, and even the most prominent have masses that are less than a few x 107 MSun, or 10-4 that of the Milky Way. All of these galaxies are moving in the potential set by the overall Local Group system, but dominated by M31 and the Milky Way. Determining full space motions for the dwarfs therefore provide a means of constraining that potential. Even though the galaxies, and their brightest stellar constituents, are faint, measuring radial velocity is a relatively straightforward procedure. Deriving tangential motions is not, since the typical proper motions of these systems are a few mas/year at best. The present proposal aims to capitalise on the exceptional resolution and high stability of HST to address this issue. Wide Field Camera 3 and the Advanced Camera for Surveys will be used to obtain first epoch observations of the 32 known dwarf galaxies within 420 kpc. that currently lack such data. These observations will lay the foundation for future observations with both HST and future missions, including JWST and WFIRST.

GO 14767: The Panchromatic Comparative Exoplanetary Treasury Program

Artist's impression of the GJ 1214 system
The first exoplanet, 51 Peg b, was discovered through radial velocity measurements in 1995. 51 Pegb was followed by a trickle, and then a flood of other discoveries, as astronomers realised that there were other solar systems radically different from our own, where "hot jupiters" led to short-period, high-amplitude velocity variations. Then, in 1999, came the inevitable discovery that one of those hot jupiters. HD 209458b, was in an orbit aligned with our line of sight to the star, resulting in transits. Since that date, the number of known transiting exoplanet systems has grown to more than 100 from ground-based observations, most detected through wide-field photometric surveys, while the high-sensitivity data provided by Kepler has added a further 1000+ confirmed systems and ~2000 additional candidates. Transiting systems not only provide an accurate measure of the planetary radius (at least relative to the parent star), they also provide us with an opportunity to probe the atmospheric composition through spectroscopy during the transit. Hubble has made significant inroads in this area, while Spitzer has contributed measurements of planetary emissivity through observations during and after eclipse. The James Webb Space Telescope has the capability to revolutionise our knowledge in this field through highly sensitiive observations at near and mid-infra red wavelengths. The present program aims to lay the foundation for those programs by using Hubble to compile multiwavelength (UV to near-IR) spectroscopic observations of 20 exoplanets. The targets are all gas giants, ranging from super-jovian masses to neptunian masses. The observations will be obtained with the Space Telescope Imaging Spectrograph and the near-infrared grisms on Wide Field Camera 3.

GO 15158: Astrometry of 2014MU69 for New Horizons encounter

Hubble Space Telescope images of the Pluto system, including the recently discovered moons, P4 and P5
The Kuiper Belt lies beyond the orbit of Neptune, extending from ~30 AU to ~50 AU from the Sun, and includes at least 70,000 objects with diameters exceeding 100 km. Setting aside Pluto, the first trans-Neptunian objects were discovered in the early 1990s. Most are relatively modest in size, with diameters of a few hundred km and photometric properties that suggest an icy composition, similar to Pluto and its main satellite, Charon. In recent years, a handful of substantially larger bodies have been discovered, with diameters of more than 1000 km; indeed, one object, Eris (2003 UB13), is slightly larger than Pluto (2320 km) and 25% more massive. We know the mass for Eris because it has a much lower mass companion, Dysnomia, which orbits Eris with a period of 16 days (see this recent press release ). The New Horizons Mission was launched on January 19th 2006 with the prime purpose of providing the first detailed examination of Pluto. Following the Pluto fly-by on Bastille day 2015, the probe has been redirected towards smaller members of the Kuiper Belt, with the goal of providing a closer look at these icy bodies. Based on Hubble imaging, a suitable prime target has been identified: 2014 MU69, a ~30 km diameter KBO lying ~44 AU from the Sun. In addition, New Horizons is expected to take longer-range, monochromatic images of up to 10 other KBOs. The present observations are being used to measure accurate positions for the prime target to refine its orbital parameters and optimize the New Horizon encounter.

GO 15262: Hubble 2020: Outer Planet Atmospheres Legacy (OPAL) Program

Global map of Jupiter from OPAL's 2015 observations
The gas giants and ice giants in the outer system have extended, dynamic gaseous atmospheres that show a range of phenomena reflecting the underlying composition and cloud structure. These are generally driven by solar insolation, with the consequence that the frequency, scale and range of features diminishes from Jupiter through saturn and Uranus to Neptune. Monitoring the changes in the wide variety of features in these atmospheres can provide insight into the velocity structrue and the energy sources. Hubble OPAL program was established in 2014 to support this type of monitoring campaign. The program targets all four outer planets for imaging with a wide range of broad and narrow-band filters on Wide Field Camera 3. The observations are spaced over two consecutive rotations, providing full longitudinal coverage for each planet. The present observations cover Uranus.

Past weeks:
page by Neill Reid, updated 31/8/2017
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