Search Publications
Star Formation Across the W3 Complex
Tapia, Mauricio; Román-Zúñiga, Carlos G.; Ybarra, Jason E. +3 more
We present a multi-wavelength analysis of the history of star formation in the W3 complex. Using deep, near-infrared ground-based images combined with images obtained with Spitzer and Chandra observatories, we identified and classified young embedded sources. We identified the principal clusters in the complex and determined their structure and ex…
The γ-Ray Detected Narrow-line Seyfert 1 Galaxy 1H 0323+342: Swift Monitoring and Suzaku Spectroscopy
Komossa, S.; Yuan, Weimin; Fuhrmann, L. +3 more
As a radio-loud narrow-line Seyfert 1 galaxy (NLS1) detected by Fermi/LAT in GeV γ-rays, 1H 0323+342 is a remarkable active galactic nucleus showing properties characteristic of both NLS1s and blazars. Here we present results of simultaneous X-ray and UV/optical monitoring observations on 1H 0323+342 taken with the UV/Optical Telescope and X-ray T…
The Far-Ultraviolet Ups and Downs of Alpha Centauri
Ayres, Thomas R.
Four years (2010-2014) of semiannual pointings by the Hubble Space Telescope Imaging Spectrograph (STIS) on nearby Alpha Centauri have yielded a detailed time history of far-ultraviolet (FUV: 1150-1700 Å) emissions of the solarlike primary (A: G2 V) and the cooler but more active secondary (B: K1 V). This period saw A climbing out of a prolonged c…
Proper Motion of the Draco Dwarf Galaxy Based On Hubble Space Telescope Imaging
Piatek, Slawomir; Pryor, Carlton; Olszewski, Edward W.
We have measured the proper motion of the Draco dwarf galaxy using images at two epochs with a time baseline of about two years taken with the Hubble Space Telescope Advanced Camera for Surveys. Wide Field Channels 1 and 2 provide two adjacent fields, each containing a known QSO. The zero point for the proper motion is determined using both backgr…
WIYN Open Cluster Study. LXVI. Spectroscopic Binary Orbits in the Young Open Cluster M35 (NGC 2168)
Gosnell, N. M.; Leiner, E. M.; Mathieu, R. D. +1 more
The young (150 Myr) open cluster M35 (NGC 2168) has been one of the core clusters of the WIYN Open Cluster Study since 1997. Over these 17 years we have obtained approximately 8000 radial-velocity (RV) measurements of stars in the M35 field, which we provide here. Our target sample consists of 1355 photometrically selected stars in the field of M3…
Enceladus’ Geysers: Relation to Geological Features
Porco, Carolyn C.; Helfenstein, Paul
We apply histogram analysis, photogeological methods, and tidal stress modeling to Porco et al.'s survey of 101 Enceladus South Polar Basin geysers and their three-dimensional orientations to test if the jet azimuths are influenced by their placement relative to surface morphology and tectonic structures. Geysers emplaced along the three most acti…
Saturn´s Inner Satellites: Orbits, Masses, and the Chaotic Motion of Atlas from New Cassini Imaging Observations
Cooper, N. J.; Murray, C. D.; Evans, M. W. +1 more
We present numerically derived orbits and mass estimates for the inner Saturnian satellites, Atlas, Prometheus, Pandora, Janus, and Epimetheus from a fit to 2580 new Cassini Imaging Science Subsystem astrometric observations spanning 2004 February to 2013 August. The observations are provided as machine-readable and Virtual Observatory tables. We …
The Flare-ona of EK Draconis
Ayres, Thomas R.
EK Draconis (HD 129333: G1.5 V) is a well-known young (50 Myr) solar analog. In 2012, Hubble Space Telescope returned to EK Dra to follow up a far-ultraviolet (FUV) SNAPshot visit by Cosmic Origins Spectrograph (COS) two years earlier. The brief SNAP pointing had found surprisingly redshifted, impulsively variable subcoronal “hot-line” emission of…
Chemical Abundances and Properties of the Ionized Gas in NGC 1705
Tosi, M.; Mignoli, M.; Aloisi, A. +3 more
We obtained [O iii] narrow-band imaging and multi-slit MXU spectroscopy of the blue compact dwarf (BCD) galaxy NGC 1705 with FORS2@VLT to derive chemical abundances of planetary nebulae and H ii regions and, more in general, to characterize the properties of the ionized gas. The auroral [O iii]λ 4363 line was detected in all but 1 of the 11 analyz…
A New Active Asteroid 313P/Gibbs
Mutchler, Max; Peixinho, Nuno; Jewitt, David +5 more
We present initial observations of the newly discovered active asteroid 313P/Gibbs (formerly P/2014 S4), taken to characterize its nucleus and comet-like activity. The central object has a radius ∼0.5 km (geometric albedo 0.05 assumed). We find no evidence for secondary nuclei and set (with qualifications) an upper limit to the radii of such objec…