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Two Planets Straddling the Habitable Zone of the Nearby K Dwarf Gl 414A
DOI: 10.3847/1538-3881/abd0ef Bibcode: 2021AJ....161...86D

Cargile, Phillip A.; Knutson, Heather A.; Pepper, Joshua +14 more

We present the discovery of two planets orbiting the nearby (D = 11.9 pc) K7 dwarf Gl 414A. Gl 414A b is a sub-Neptune mass planet with ${M}_{b}\sin {i}_{b}={7.60}_{-2.19}^{+2.44}$ M and a semimajor axis of 0.23 ± 0.01 au. Gl 414A c is a sub-Saturn mass planet with ${M}_{c}\sin {i}_{c}={53.83}_{-8.58}^{+9.18}$ M and a semim…

2021 The Astronomical Journal
Gaia 11
ACCESS: An Optical Transmission Spectrum of the High-gravity Hot Jupiter HAT-P-23b
DOI: 10.3847/1538-3881/abf652 Bibcode: 2021AJ....161..278W

Kirk, James; López-Morales, Mercedes; MacDonald, Ryan J. +11 more

We present a new ground-based visible transmission spectrum of the high-gravity, hot Jupiter HAT-P-23b, obtained as part of the ACCESS project. We derive the spectrum from five transits observed between 2016 and 2018, with combined wavelength coverage between 5200 Å and 9269 Å in 200 Å bins, and with a median precision of 247 ppm per bin. HAT-P-23…

2021 The Astronomical Journal
Gaia 11
Distance and Mass of the NGC 253 Galaxy Group
DOI: 10.3847/1538-3881/abe8d1 Bibcode: 2021AJ....161..205K

Anand, Gagandeep S.; Shaya, Edward J.; Tully, R. Brent +2 more

Two dwarf galaxies, WOC2017-07 and PGC 704814, located in the vicinity of the nearby luminous spiral galaxy NGC 253 were observed with the Advanced Camera for Surveys on the Hubble Space Telescope. Their distances of 3.62 ± 0.18 Mpc and 3.66 ± 0.18 Mpc were derived using the tip of the red giant branch method. These distances are consistent with t…

2021 The Astronomical Journal
eHST 11
Photometric and Kinematic Study of the Open Clusters SAI 44 and SAI 45
DOI: 10.3847/1538-3881/ac0138 Bibcode: 2021AJ....162...64M

Sharma, Saurabh; Joshi, Y. C.; Elsanhoury, W. H. +1 more

We carry out a detailed photometric and kinematic study of the poorly studied sparse open clusters SAI 44 and SAI 45 using ground-based BVRcIc data supplemented by archival data from Gaia eDR3 and Pan-STARRS. The stellar memberships are determined using a statistical method based on Gaia eDR3 kinematic data, and we found 204 …

2021 The Astronomical Journal
Gaia 11
The White Dwarfs of the Old, Solar-metallicity Open Star Cluster Messier 67: Properties and Progenitors
DOI: 10.3847/1538-3881/abe1ad Bibcode: 2021AJ....161..169C

Kilic, Mukremin; Bolte, Michael; Canton, Paul A. +1 more

The old, solar-metallicity open cluster Messier 67 has long been considered a lynchpin in the study and understanding of the structure and evolution of solar-type stars. The same is arguably true for stellar remnants; the white dwarf population of M67 provides crucial observational data for understanding and interpreting white dwarf populations an…

2021 The Astronomical Journal
Gaia 11
K2-138 g: Spitzer Spots a Sixth Planet for the Citizen Science System
DOI: 10.3847/1538-3881/abeab0 Bibcode: 2021AJ....161..219H

Kristiansen, Martti H.; Barclay, Thomas; Gorjian, Varoujan +10 more

K2 greatly extended Kepler's ability to find new planets, but it was typically limited to identifying transiting planets with orbital periods below 40 days. While analyzing K2 data through the Exoplanet Explorers project, citizen scientists helped discover one super-Earth and four sub-Neptune sized planets in the relatively bright (V = 12.21, K = …

2021 The Astronomical Journal
Gaia 11
TOI-954 b and K2-329 b: Short-period Saturn-mass Planets that Test whether Irradiation Leads to Inflation
DOI: 10.3847/1538-3881/abd187 Bibcode: 2021AJ....161...82S

Henning, Thomas; Vanderburg, Andrew; Bieryla, Allyson +70 more

We report the discovery of two short-period Saturn-mass planets, one transiting the G subgiant TOI-954 (TIC 44792534, V = 10.343, T = 9.78) observed in TESS sectors 4 and 5 and one transiting the G dwarf K2-329 (EPIC 246193072, V = 12.70, K = 10.67) observed in K2 campaigns 12 and 19. We confirm and characterize these two planets with a variety of…

2021 The Astronomical Journal
Gaia 11
Ground-based Transmission Spectroscopy with VLT FORS2: Evidence for Faculae and Clouds in the Optical Spectrum of the Warm Saturn WASP-110b
DOI: 10.3847/1538-3881/ac01da Bibcode: 2021AJ....162...88N

Madhusudhan, Nikku; Nikolov, Nikolay; Maciejewski, Gracjan +12 more

We present a ground-based optical transmission spectrum for the warm Saturn-mass exoplanet WASP-110b from two transit observations made with the FOcal Reducer and Spectrograph on the Very Large Telescope. The spectrum covers the wavelength range from 4000-8333 Å, which is binned in 46 transit depths measured to an averaged precision of 220 parts p…

2021 The Astronomical Journal
Gaia 11
The Age-Metallicity-Specific Orbital Energy Relation for the Milky Way's Globular Cluster System Confirms the Importance of Accretion for Its Formation
DOI: 10.3847/1538-3881/abff5f Bibcode: 2021AJ....162...42W

Schlaufman, Kevin C.; Woody, Turner

Globular clusters can form inside their host galaxies at high redshift when gas densities are higher and gas-rich mergers are common. They can also form inside lower-mass galaxies that have since been accreted and tidally disrupted, leaving their globular cluster complement bound to higher-mass halos. We argue that the age-metallicity-specific orb…

2021 The Astronomical Journal
Gaia 11
How Complete Are Surveys for Nearby Transiting Hot Jupiters?
DOI: 10.3847/1538-3881/ac2958 Bibcode: 2021AJ....162..240Y

Winn, Joshua N.; Hartman, Joel D.; Yee, Samuel W.

Hot Jupiters are a rare and interesting outcome of planet formation. Although more than 500 hot Jupiters (HJs) are known, most of them were discovered by a heterogeneous collection of surveys with selection biases that are difficult to quantify. Currently, our best knowledge of HJ demographics around FGK stars comes from the sample of ≈40 objects …

2021 The Astronomical Journal
Gaia 11