Results 1 to 10 of about 252 (123)
Evidence for Water in the Rocky Debris of a Disrupted Extrasolar Minor Planet [PDF]
Science, 2013 Remnants of a Water-Bearing World Stars like the Sun end their lives as white dwarfs. Farihi et al. (p. 218 ) used detailed spectroscopic analysis of a debris-accreting white dwarf, along with knowledge that such systems accrete this debris ...
J. Farihi, B. T. Gansicke, D. Koester
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CHEMICAL ABUNDANCES IN THE EXTERNALLY POLLUTED WHITE DWARF GD 40: EVIDENCE OF A ROCKY EXTRASOLAR MINOR PLANET [PDF]
The Astrophysical Journal, 2010 We present Keck/HIRES data with model atmosphere analysis of the helium-dominated polluted white dwarf GD 40, in which we measure atmospheric abundances relative to helium of 9 elements: H, O, Mg, Si, Ca, Ti, Cr, Mn, and Fe. Apart from hydrogen whose association with the other contaminants is uncertain, this material most likely accreted from GD 40's ...
Klein, B. +4 more
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Potential Atmospheric Compositions of TRAPPIST-1 c Constrained by JWST/MIRI Observations at 15 μm
The Astrophysical Journal Letters, 2023 The first James Webb Space Telescope observations of TRAPPIST-1 c showed a secondary eclipse depth of 421 ± 94 ppm at 15 μ m, which is consistent with a bare rock surface or a thin, O _2 -dominated, low-CO _2 atmosphere. Here we further explore potential
Andrew P. Lincowski +15 more
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The Carbon-deficient Evolution of TRAPPIST-1c
The Astrophysical Journal, 2023 Transiting planets orbiting M dwarfs provide the best opportunity to study the atmospheres of rocky planets with current facilities. As JWST enters its second year of science operations, an important initial endeavor is to determine whether these rocky ...
Katie E. Teixeira +3 more
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Alternative Methylated Biosignatures. I. Methyl Bromide, a Capstone Biosignature
The Astrophysical Journal, 2022 The first potential exoplanetary biosignature detections are likely to be ambiguous due to the potential for false positives: abiotic planetary processes that produce observables similar to those anticipated from a global biosphere.
Michaela Leung +3 more
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Measuring the Obliquities of the TRAPPIST-1 Planets with MAROON-X
The Astronomical Journal, 2023 A star’s obliquity with respect to its planetary system can provide us with insight into the system’s formation and evolution, as well as hinting at the presence of additional objects in the system. However, M dwarfs, which are the most promising targets
Madison Brady +8 more
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The Astronomical Journal, 2023 Binary stars are ubiquitous; the majority of solar-type stars exist in binaries. Exoplanet occurrence rate is suppressed in binaries, but some multiples do still host planets.
Kendall Sullivan +9 more
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The Astronomical Journal, 2023 The radius valley carries implications for how the atmospheres of small planets form and evolve, but this feature is visible only with highly precise characterizations of many small planets.
Dominic Oddo +43 more
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The Direct Mid-infrared Detectability of Habitable-zone Exoplanets around Nearby Stars
The Astronomical Journal, 2023 Giant planets within the habitable zones of the closest several stars can currently be imaged with ground-based telescopes. Within the next decade, the Extremely Large Telescopes (ELTs) will begin to image the habitable zones of a greater number of ...
Zach Werber, Kevin Wagner, Dániel Apai
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Detecting Solar System Analogs through Joint Radial Velocity/Astrometric Surveys
The Astronomical Journal, 2023 Earth-mass exoplanets on year-long orbits and cool gas giants (CGG) on decade-long orbits lie at the edge of current detection limits. The Terra Hunting Experiment (THE) will take nightly radial velocity (RV) observations on HARPS3 of at least 40 bright ...
Daniel A. Yahalomi +3 more
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