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A Morphological Classification Model to Identify Unresolved PanSTARRS1 Sources. II. Update to the PS1 Point Source Catalog
Miller, A. A.; Hall, X. J.
We present an update to the PanSTARRS-1 Point Source Catalog (PS1 PSC), which provides morphological classifications of PS1 sources. The original PS1 PSC adopted stringent detection criteria that excluded hundreds of millions of PS1 sources from the PSC. Here, we adapt the supervised machine learning methods used to create the PS1 PSC and apply th…
Interstellar Extinction and Polarization of Stars in the Open Cluster NGC 7160
Topasna, G. A.; Riley, R. W.; Kaltcheva, N. T.
We present polarimetric observations of stars in the field of the open cluster NGC 7160. The multi-wavelength UBVRI polarization measurements of 21 stars that we performed indicate that some of the observed stars follow the typical wavelength dependence indicative of polarization by selective extinction in the interstellar medium, while others dis…
Trigonometric Parallaxes of Two T Dwarfs With Keck and ShaneAO Astrometry
Lu, Jessica R.; Ammons, S. Mark; Nguyen, Jayke +4 more
We present trigonometric parallax and proper motion measurements for two T-type brown dwarfs. We derive our measurements from infrared laser guide star adaptive optics observations spanning five years from the ShaneAO/SHARCS and NIRC2/medium-cam instruments on the Shane and Keck telescopes, respectively. To improve our astrometric precision, we me…
Infrared Emission Properties of Active Galactic Nuclei from Swift-BAT Hard X-Ray Survey
Yang, Xiao-Hong
The Swift/Burst Alert Telescope (BAT) 105-month survey detected 1632 hard X-ray sources in the 14-195 keV band, which includes 1105 active galactic nuclei (AGNs) that are unbiased against Compton-thin obscuration. We use a series of two-color diagrams to analyze the near, mid (MIR), and far-infrared properties of the Swift/BAT AGNs, based on data …
Lost in Space? Relativistic Interstellar Navigation using an Astrometric Star Catalog
Bailer-Jones, Coryn A. L.
The exploration of interstellar space will require autonomous navigation systems that do not rely on tracking from the Earth. Here I develop a method to determine the 3D position and 3D velocity of a spacecraft in deep space using a star catalog. As a spacecraft moves away from the Sun, the observed positions and velocities of the stars will chang…