Search Publications
Models of Rosetta/OSIRIS 67P Dust Coma Phase Function
Lamy, P. L.; Lara, L. M.; Bertaux, J. -L. +39 more
The phase function of the dust coma of comet 67P has been determined from Rosetta/OSIRIS images. This function shows a deep minimum at phase angles near 100°, and a strong backscattering enhancement. These two properties cannot be reproduced by regular models of cometary dust, most of them based on wavelength-sized and randomly oriented aggregate …
Binary Red Supergiants: A New Method for Detecting B-type Companions
Massey, Philip; Levesque, Emily M.; Neugent, Kathryn F.
With the exception of a few well-known and studied systems, the binary population of red supergiants (RSGs) remains relatively uncharacterized. Famous systems such as VV Cep, 31 Cyg, and ζ Aur contain RSG + B star binaries, and here we explore whether B stars are the main type of companion we expect from an evolutionary point of view. Using the Ge…
Li in Open Clusters: Cool Dwarfs in the Young, Subsolar-metallicity Cluster M35 (NGC 2168)
Twarog, Bruce A.; Anthony-Twarog, Barbara J.; Deliyannis, Constantine P. +4 more
Hydra spectra of 85 G-K dwarfs in the young cluster M35 near the Li 6708 Å line region are analyzed. From velocities and Gaia astrometry, 78 are likely single-star members that, combined with previous work, produce 108 members with T eff ranging from 6150 to 4000 K as defined by multicolor, broadband photometry, E(B - V) = 0.20, and [Fe…
Cepheids in M31: The PAndromeda Cepheid Sample
Lee, Chien-Hsiu; Bender, Ralf; Seitz, Stella +15 more
We present the largest Cepheid sample in M31 based on the complete Pan-STARRS1 survey of Andromeda (PAndromeda) in the r P1, i P1, and g P1 bands. We find 2686 Cepheids with 1662 fundamental-mode Cepheids, 307 first-overtone Cepheids, 278 type II Cepheids, and 439 Cepheids with undetermined Cepheid type. Using the …
The Nucleus of Active Asteroid 311P/(2013 P5) PANSTARRS
Mutchler, Max; Jewitt, David; Agarwal, Jessica +3 more
The unique inner-belt asteroid 311P/PANSTARRS (formerly P/2013 P5) is notable for its sporadic, comet-like ejection of dust in nine distinct epochs spread over ∼250 days in 2013. This curious behavior has been interpreted as the product of localized, equatorward landsliding from the surface of an asteroid rotating at the brink of instability. We o…
Zodiacal Light Beyond Earth Orbit Observed with Pioneer 10
Matsumoto, T.; Pyo, J.; Tsumura, K. +1 more
We reanalyze the Imaging Photopolarimeter data from Pioneer 10 to study the zodiacal light in the B and R bands beyond Earth orbit, applying an improved method to subtract integrated star light (ISL) and diffuse Galactic light (DGL). We found that there exists a significant instrumental offset, making it difficult to examine the absolute sky brigh…
The High Cadence Transit Survey (HiTS): Compilation and Characterization of Light-curve Catalogs
Pignata, Giuliano; Galbany, Lluis; González-Gaitán, Santiago +12 more
The High Cadence Transient Survey (HiTS) aims to discover and study transient objects with characteristic timescales between hours and days, such as pulsating, eclipsing, and exploding stars. This survey represents a unique laboratory to explore large etendue observations from cadences of about 0.1 days and test new computational tools for the ana…
LHS 1610A: A Nearby Mid-M Dwarf with a Companion That Is Likely a Brown Dwarf
Latham, David W.; Berlind, Perry; Calkins, Michael L. +7 more
We present the spectroscopic orbit of LHS 1610A, a newly discovered single-lined spectroscopic binary with a trigonometric distance placing it at 9.9 ± 0.2 pc. We obtained spectra with the TRES instrument on the 1.5 m Tillinghast Reflector at the Fred Lawrence Whipple Observatory located on Mt. Hopkins in AZ. We demonstrate the use of the TiO mole…
URAT South Parallax Results
Jao, Wei-Chun; Finch, Charlie T.; Zacharias, Norbert
We present 916 trigonometric parallaxes and proper motions of newly discovered nearby stars from the United States Naval Observatory Robotic Astrometric Telescope (URAT). Observations were taken at the Cerro Tololo Interamerican Observatory over a 2-year period from 2015 to 2017 October covering the entire sky south of about +25° decl. SPM4 and UC…
Deep Hubble Space Telescope Imaging of Globular Clusters toward the Galactic Bulge: Observations, Data Reduction, and Color-magnitude Diagrams
Cohen, Roger E.; Sarajedini, Ata; Hempel, Maren +5 more
The Galactic globular clusters (GGCs) located toward the Galactic bulge have generally been excluded from large-scale photometric GGC surveys due to severe total and differential extinction. Here we present an overview of a Hubble Space Telescope (HST) program designed to obtain deep, high spatial resolution multiband imaging of 16 poorly studied …