Search Publications
Toward Precise Stellar Ages: Combining Isochrone Fitting with Empirical Gyrochronology
Hogg, David W.; Angus, Ruth; Morton, Timothy D. +7 more
We present a new age-dating technique that combines gyrochronology with isochrone fitting to infer ages for FGKM main-sequence and subgiant field stars. Gyrochronology and isochrone fitting are each capable of providing relatively precise ages for field stars in certain areas of the Hertzsprung-Russell diagram (HRD): gyrochronology works optimally…
A Second Terrestrial Planet Orbiting the Nearby M Dwarf LHS 1140
Latham, David W.; Esquerdo, Gilbert A.; Tan, Thiam-Guan +27 more
LHS 1140 is a nearby mid-M dwarf known to host a temperate rocky super-Earth (LHS 1140 b) on a 24.737-day orbit. Based on photometric observations by MEarth and Spitzer as well as Doppler spectroscopy from the High Accuracy Radial velocity Planet Searcher, we report the discovery of an additional transiting rocky companion (LHS 1140 c) with a mass…
A Hot Saturn Orbiting an Oscillating Late Subgiant Discovered by TESS
Henning, Thomas; Smalley, Barry; Chaplin, William J. +139 more
We present the discovery of HD 221416 b, the first transiting planet identified by the Transiting Exoplanet Survey Satellite (TESS) for which asteroseismology of the host star is possible. HD 221416 b (HIP 116158, TOI-197) is a bright (V = 8.2 mag), spectroscopically classified subgiant that oscillates with an average frequency of about 430 µ…
Dust Unveils the Formation of a Mini-Neptune Planet in a Protoplanetary Ring
Dong, Ruobing; Baruteau, Clément; Pérez, Sebastián +3 more
Rings and radial gaps are ubiquitous in protoplanetary disks, yet their possible connection to planet formation is currently subject to intense debates. In principle, giant planet formation leads to wide gaps that separate the gas and dust mass reservoir in the outer disk, while lower mass planets lead to shallow gaps that are manifested mainly on…
Hot Jupiters Are Destroyed by Tides While Their Host Stars Are on the Main Sequence
Schlaufman, Kevin C.; Hamer, Jacob H.
While cooler giant planets are often observed with nonzero eccentricities, the short-period circular orbits of hot Jupiters suggest that they lose orbital energy and angular momentum due to tidal interactions with their host stars. However, orbital decay has never been unambiguously observed. We use data from Gaia Data Release 2 to show that hot J…
TESS Reveals that the Nearby Pisces-Eridanus Stellar Stream is only 120 Myr Old
Wright, Jason T.; Cummings, Jeffrey D.; Mamajek, Eric E. +2 more
Pisces-Eridanus (Psc-Eri), a nearby (d ≃ 80-226 pc) stellar stream stretching across ≈120° of the sky, was recently discovered with Gaia data. The stream was claimed to be ≈1 Gyr old, which would make it an exceptional discovery for stellar astrophysics, as star clusters of that age are rare and tend to be distant, limiting their utility as benchm…
Spitzer Phase Curves of KELT-1b and the Signatures of Nightside Clouds in Thermal Phase Observations
Fortney, Jonathan J.; Showman, Adam P.; Marley, Mark S. +3 more
We observed two full orbital phase curves of the transiting brown dwarf KELT-1b, at 3.6 and 4.5 µm, using the Spitzer Space Telescope. Combined with previous eclipse data from Beatty et al., we strongly detect KELT-1b’s phase variation as a single sinusoid in both bands, with amplitudes of 964 ± 36 ppm at 3.6 µm and 979 ± 54 ppm at 4.5…
Three Red Suns in the Sky: A Transiting, Terrestrial Planet in a Triple M-dwarf System at 6.9 pc
Barclay, Thomas; Latham, David W.; Berlind, Perry +40 more
We present the discovery from Transiting Exoplanet Survey Satellite (TESS) data of LTT 1445Ab. At a distance of 6.9 pc, it is the second nearest transiting exoplanet system found to date, and the closest one known for which the primary is an M dwarf. The host stellar system consists of three mid-to-late M dwarfs in a hierarchical configuration, wh…
Discovery of a Third Transiting Planet in the Kepler-47 Circumbinary System
Torres, Guillermo; Cochran, William D.; Endl, Michael +16 more
Of the nine confirmed transiting circumbinary planet systems, only Kepler-47 is known to contain more than one planet. Kepler-47 b (the “inner planet”) has an orbital period of 49.5 days and a radius of about 3 R ⊕. Kepler-47 c (the “outer planet”) has an orbital period of 303.2 days and a radius of about 4.7 R ⊕. Here we rep…
A Warm Jupiter-sized Planet Transiting the Pre-main-sequence Star V1298 Tau
Hinkley, Sasha; Fulton, Benjamin J.; Isaacson, Howard T. +14 more
We report the detection of V1298 Tau b, a warm Jupiter-sized planet (R P = 0.91 ± 0.05 R Jup, P = 24.1 days) transiting a young solar analog with an estimated age of 23 Myr. The star and its planet belong to Group 29, a young association in the foreground of the Taurus-Auriga star-forming region. While hot Jupiters have been …