Architectures of Exoplanetary Systems. III. Eccentricity and Mutual Inclination Distributions of AMD-stable Planetary Systems [PDF]
Astronomical Journal, 2020 The angular momentum deficit (AMD) of a planetary system is a measure of its orbital excitation and a predictor of long-term stability. We adopt the AMD-stability criterion to constrain the orbital architectures for exoplanetary systems.
M. He, E. Ford, D. Ragozzine, D. Carrera
semanticscholar +1 more source
The protoplanetary disc HD 163296 as observed by ALMA
Vietnam Journal of Science, Technology and Engineering, 2022 HD 163296 is one of the few protoplanetary discs displaying rings in the dust component. The present work uses ALMA observations of the 0.9 mm continuum emission, which have significantly better spatial resolution (~8 au) than previously available, to ...
P.N. Diep +6 more
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Universe, 2022 Only a low percentage of the radiation from our Sun is captured by photosynthesis, but this conversion of solar to chemical energy sustains all life on Earth.
Pablo Marcos-Arenal +7 more
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Two Young Planetary Systems around Field Stars with Ages between 20 and 320 Myr from TESS [PDF]
Astronomical Journal, 2020 Planets around young stars trace the early evolution of planetary systems. We report the discovery and validation of two planetary systems with ages ≲300 Myr from observations by the Transiting Exoplanet Survey Satellite (TESS).
G. Zhou +48 more
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The Planetary Theory of Solar Activity Variability: A Review
Frontiers in Astronomy and Space Sciences, 2022 Commenting the 11-year sunspot cycle, Wolf (1859, MNRAS 19, 85–86) conjectured that “the variations of spot-frequency depend on the influences of Venus, Earth, Jupiter, and Saturn.” The high synchronization of our planetary system is already nicely ...
Nicola Scafetta, Antonio Bianchini
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Dynamics of Planetary Systems within Star Clusters: Aspects of the Solar System’s Early Evolution [PDF]
Astronomical Journal, 2020 Most planetary systems—including our own—are born within stellar clusters, where interactions with neighboring stars can help shape the system architecture. This paper develops an orbit-averaged formalism to characterize the cluster’s mean-field effects,
K. Batygin +3 more
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Normalized angular momentum deficit: a tool for comparing the violence of the dynamical histories of planetary systems [PDF]
Astronomy & Astrophysics, 2020 Context. Population studies of the orbital characteristics of exoplanets in multi-planet systems have highlighted the existence of an anticorrelation between the average orbital eccentricity of planets and the number of planets of their host system, that
D. Turrini, A. Zinzi, J. A. Belinchón
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The formation of planetary systems with SPICA [PDF]
Publications of the Astronomical Society of Australia, 2021 Abstract In this era of spatially resolved observations of planet-forming disks with Atacama Large Millimeter Array (ALMA) and large ground-based telescopes such as the Very Large Telescope (VLT), Keck, and Subaru, we still lack statistically relevant information on the quantity and composition of the material that is building the planets, such as ...
Kamp, I. +40 more
openaire +9 more sources
Modeling optical and UV polarization of AGNs. I. Imprints of individual scattering regions [PDF]
, 2005 Context. Spectropolarimetry of AGNs is a powerful tool for studying the structure and kinematics of the inner regions of quasars. Aims. We wish to investigate the effects of various AGN scattering region geometries on the polarized flux. Methods.
R. Goosmann +12 more
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The JWST Early-release Science Program for Direct Observations of Exoplanetary Systems II: A 1 to 20 μm Spectrum of the Planetary-mass Companion VHS 1256–1257 b [PDF]
Astrophysical Journal Letters, 2022 We present the highest fidelity spectrum to date of a planetary-mass object. VHS 1256 b is a
B. Miles +110 more
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