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A Jupiter Analog Orbiting The Nearby M Dwarf GJ 463
Cochran, William D.; Endl, Michael; Howard, Andrew W. +8 more
We report the detection of a long-period giant planetary companion to the nearby M3V star GJ 463 (=Ross 690). The detection is based on over ten years of highly-precise radial velocity measurements with the High Resolution Spectrograph at the Hobby-Eberly Telescope and the HIRES spectrograph at Keck. With an orbital period of 10 yr and a minimum m…
Milliarcsecond Astrometry for the Galilean Moons Using Stellar Occultations
Aoki, S.; Smith, M.; Carlson, R. W. +40 more
A stellar occultation occurs when a Solar System object passes in front of a star for an observer. This technique allows the sizes and shapes of the occulting body to be determined with kilometer precision. In addition, this technique constrains the occulting body's positions, albedos, densities, and so on. In the context of the Galilean moons, th…
3D Orbital Architecture of a Dwarf Binary System and Its Planetary Companion
Curiel, Salvador; Sanchez-Bermudez, Joel; Ortiz-León, Gisela N. +1 more
Because of the diversity of stellar masses and orbital sizes of binary systems and the complex interaction between star-star, star-planet, and planet-planet, it has been difficult to fully characterize the planetary systems associated with binary systems. Here, we report high-precision astrometric observations of the low-mass binary system GJ 896A…
The Family of V1311 Ori: a Young Sextuple System or a Minicluster?
Tokovinin, Andrei
A compact bound group of four active M-type dwarfs containing V1311 Ori is identified in the Gaia catalog of nearby stars. Located at a distance of 39 pc, it is likely related to the β Pictoris and 32 Ori moving groups by kinematics, isochronal age, and other indicators of youth (Hα emission, presence of lithium, and fast rotation). The brightest …
Around the Spindle Galaxy: The Dark Halo Mass of NGC 3115
Karachentsev, I. D.; Anand, G. S.; Makarova, L. N. +1 more
We report observations of five dwarf galaxies in the vicinity of the luminous S0 galaxy NGC 3115 performed with the Advanced Camera for Surveys on the Hubble Space Telescope. Their distances determined via the Tip of the Red Giant Branch are: 10.05 Mpc (UGCA 193), 9.95 Mpc (KKSG 17), 10.13 Mpc (2MASX-J0957-0915), 10.42 Mpc (2dFGRS-TGN218Z179), and…
Detection of Na and K in the Atmosphere of the Hot Jupiter HAT-P-1b with P200/DBSP
Wang, Hongchi; van Boekel, Roy; Chen, Guo +1 more
We present a new optical transmission spectrum of the hot Jupiter HAT-P-1b based on two transits observed with the Double Spectrograph (DBSP) on the Palomar 200-inch (P200) telescope. The DBSP transmission spectrum, covering a wavelength range from 3250 to 10007 Å, is consistent with that observed with the Hubble Space Telescope (HST), but the for…
A Comprehensive Study of Five Intermediate-age Pismis (2, 3, 7, 12, 15) Clusters Using Photometric and Astrometric Data from Gaia EDR3
Bisht, D.; Rangwal, Geeta; Yadav, R. K. S. +5 more
Open clusters are groups of stars that form simultaneously; hence, these are excellent probes to test theories of star formation, stellar evolution, and dynamics in the Milky Way disk. We carry out a detailed photometric and kinematic study of five poorly studied intermediate-age open clusters, Pismis 2 (Pi 2), Pismis 3 (Pi 3), Pismis 7 (Pi 7), Pi…
K2-79b and K2-222b: Mass Measurements of Two Small Exoplanets with Periods beyond 10 days that Overlap with Periodic Magnetic Activity Signals
Vanderburg, Andrew; López-Morales, Mercedes; Bieryla, Allyson +28 more
We present mass and radius measurements of K2-79b and K2-222b, two transiting exoplanets orbiting active G-type stars observed with HARPS-N and K2. Their respective 10.99 day and 15.39 day orbital periods fall near periods of signals induced by stellar magnetic activity. The two signals might therefore interfere and lead to an inaccurate estimate …
Confirmation of the Long-period Planet Orbiting Gliese 411 and the Detection of a New Planet Candidate
Rosenthal, Lee J.; Howard, Andrew W.; Petigura, Erik A. +4 more
We perform a detailed characterization of the planetary system orbiting the bright, nearby M dwarf Gliese 411 using radial velocities gathered by APF, HIRES, SOPHIE, and CARMENES. We confirm the presence of a signal with a period near 2900 days that has been disputed as either a planet or a long-period stellar magnetic cycle. An analysis of activi…
The µ Arae Planetary System: Radial Velocities and Astrometry
McArthur, B. E.; Benedict, G. F.; Nelan, E. P. +4 more
With Hubble Space Telescope Fine Guidance Sensor astrometry and published and previously unpublished radial velocity measures, we explore the exoplanetary system µ Arae. Our modeling of the radial velocities results in improved orbital elements for the four previously known components. Our astrometry contains no evidence for any known compan…