Results 1 to 10 of about 151 (91)
Interstellar Comets from Post-main-sequence Systems as Tracers of Extrasolar Oort Clouds
The Planetary Science Journal, 2023 Interstellar small bodies are unique probes into the histories of exoplanetary systems. One hypothesized class of interlopers are “Jurads,” exocomets released into the Milky Way during the post-main-sequence as the thermally pulsing asymptotic giant ...
W. Garrett Levine +6 more
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Is the Hubble Crisis Connected with the Extinction of Dinosaurs?
Universe, 2022 It has recently been suggested that a gravitational transition of the effective Newton’s constant Geff by about 10%, 50–150 Myrs ago could lead to the resolution of both the Hubble crisis and the growth tension of the standard ΛCDM model.
Leandros Perivolaropoulos
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Is the Recently Proposed Mars-Sized Perturber at 65–80 AU Ruled Out by the Cassini Ranging Data?
Frontiers in Astronomy and Space Sciences, 2017 Recently, the existence of a pointlike pertuber PX with 1 m♂ ≲ mX ≲ 2.4 m⊕ (the symbol “♂” denotes Mars) supposedly moving at 65–80 AU along a moderately inclined orbit has been hypothesized in order to explain certain features of the midplane of the ...
Lorenzo Iorio
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Astronomy & AstrophysicsMost stars form in dense stellar environments, where frequent close encounters can strongly perturb and reshape the early architecture of planetary systems.
Torres Santiago
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Astronomy & AstrophysicsAims. We investigated the influence of cluster environments on asteroids, with particular attention to captured material. Methods. Using numerical methods, we simulated a sub-virial fractally distributed star-forming region and a virialised Plummer ...
Hochart E., Portegies Zwart S.
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An Efficient Observational Strategy for the Detection of the Oort Cloud
The Astronomical JournalThe Oort cloud is presumably a pristine relic of the solar system formation. Detection of the Oort cloud may provide information regarding the stellar environment in which the Sun was born and on the planetesimal population during the outer planets ...
Eran O. Ofek, Sarah A. Spitzer, Guy Nir
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A Spiral Structure in the Inner Oort Cloud
The Astrophysical JournalAs the Galactic tide acts to decouple bodies from the scattered disk it creates a spiral structure in physical space that is roughly 15,000 au in length. The spiral is long-lived and persists in the inner Oort cloud to the present time.
David Nesvorný +7 more
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Capture of interstellar objects during stellar encounters
Astronomy & AstrophysicsAs they orbit within the Galaxy, stars swim through a vast population of interstellar objects (ISOs). In this paper, we use N-body simulations to show that a fraction of ISOs within ∼1 pc of the Sun (its tidal radius) may be captured during the flyby of ...
Raymond Sean N. +2 more
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Nearby Supernova and Cloud Crossing Effects on the Orbits of Small Bodies in the Solar System
The Astrophysical Journal LettersSupernova (SN) blasts envelop many surrounding stellar systems, transferring kinetic energy to small bodies in the systems. Geologic evidence from ^60 Fe points to recent nearby SN activity within the past several Myr.
Leeanne Smith +2 more
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Oort Cloud Comets: Perturbations Due to the Passage of Gliese 710
UniverseThe outermost region of the Solar System is called the Oort cloud, which is the Solar System’s reservoir of long-period comets that extends to distances up to 200,000 au from the Sun.
Elke Pilat-Lohinger +2 more
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