Results 11 to 20 of about 15,045 (53)
The Astronomical JournalIntermediate-mass black holes (IMBHs) are believed to be the missing link between the supermassive black holes (BHs) found at the centers of massive galaxies and BHs formed through stellar core collapse. One of the proposed mechanisms for their formation
Rujuta A. Purohit +4 more
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The Astronomical JournalWe report the identification of 89 new systems containing ultracool dwarf companions to main-sequence stars and white dwarfs, using the citizen science project Backyard Worlds: Planet 9 and cross-reference between Gaia and CatWISE2020.
Austin Rothermich +45 more
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Estimating Galaxy Parameters with Self-organizing Maps and the Effect of Missing Data
The Astronomical JournalThe current and upcoming large data volume galaxy surveys require the use of machine-learning techniques to maximize their scientific return. This study explores the use of Self-Organizing Maps (SOMs) to estimate galaxy parameters with a focus on ...
Valentina La Torre +6 more
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LHS 475 b: A Potential Venus Analog Orbiting a Nearby M Dwarf
The Astronomical JournalBased on photometric observations by TESS, we present the discovery of a potential Venus analog transiting LHS 475, an M3 dwarf located 12.5 pc from the Sun. The mass of the star is 0.274 ± 0.015 M _☉ .
Kristo Ment +17 more
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The Stellar Content of the Young Open Cluster Berkeley 50 (IC 1310)
The Astronomical JournalWe observed the Galactic open cluster Berkeley 50 in order to determine its stellar content, distance, and age. We obtained UBV photometry of 1145 stars in a 12.′3 × 12.′3 field, and used Gaia proper motions and parallaxes to identify 64 members, of ...
Meghan Speckert +2 more
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The Planetary Science JournalUltraviolet spectroscopy is a powerful method to study planetary surface composition through reflectance measurements, atmospheric composition through stellar/solar occultations, transits of other planetary bodies, and direct imaging of airglow and ...
Michael A. Velez +11 more
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Detecting Exoplanets Closer to Stars with Moderate Spectral Resolution Integral-field Spectroscopy
The Astronomical Journal, 2023 While radial velocity surveys have demonstrated that the population of gas giants peaks around 3 au, the most recent high-contrast imaging surveys have only been sensitive to planets beyond ∼10 au.
Shubh Agrawal +12 more
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Active Stars in the Spectroscopic Survey of Mid-to-late M Dwarfs within 15 pc
The Astronomical Journal, 2023 We present results from the volume-complete spectroscopic survey of 0.1–0.3 M _⊙ M dwarfs within 15 pc. This work discusses the active sample without close binary companions, providing a comprehensive picture of these 123 stars with H α emission stronger
Emily K. Pass +4 more
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The Discovery and Follow-up of Four Transiting Short-period Sub-Neptunes Orbiting M Dwarfs
The Astronomical JournalSub-Neptunes with radii of 2–3 R _⊕ are intermediate in size between rocky planets and Neptune-sized planets. The orbital properties and bulk compositions of transiting sub-Neptunes provide clues to the formation and evolution of close-in small planets ...
Yasunori Hori +102 more
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Inferring the Rate of Technosignatures from 60 yr of Nondetection
The Astronomical Journal, 2023 For about the last 60 yr the search for extraterrestrial intelligence has been monitoring the sky for evidence of remotely detectable technological life beyond Earth, with no positive results to date.
Claudio Grimaldi
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