Results 1 to 10 of about 280 (117)
Deep learning-enabled size estimation of comets indicates a more dynamic early solar system [PDF]
Nature CommunicationsThe formation and evolution of the Solar System’s two major comet reservoirs, the Oort Cloud and the Scattered Disk, remain poorly constrained. Observations of comet flux imply a population ratio between these reservoirs that exceeds predictions from ...
Shunjing Zhao +4 more
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On the coincidence between the close passage of HD7977 and the Pliocene-Pleistocene transition [PDF]
Scientific ReportsThe Oort Cloud’s dynamical evolution is significantly influenced by both the galactic tide and stellar flybys. This study investigates the particular case of HD7977’s close encounter 2.47 Myr ago, which likely repopulated the Inner Oort Cloud and ...
Zhuoya Cao, Abraham Loeb, Morgan MacLeod
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Re-recognized universality of Kozai oscillation on three-body dynamics [PDF]
Proceedings of the Japan Academy. Series B, Physical and Biological SciencesIn 1962, Yoshihide Kozai reported his findings on the secular dynamics of asteroids moving in orbits with high inclination and eccentricity. In contrast to the classic understanding of the stability of planetary motion in the solar system, Kozai showed ...
Masanori IYE, Takashi ITO
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Detectability of Sungrazing Comet Soft X-ray Irradiance [PDF]
Journal of Astronomy and Space Sciences, 2007 Originating from the Oort cloud, some comets disappear to impact against the Sun or to split up by strong gravitational force. Then they don't go back to the Oort cloud. They are called sungrazing comets.
Su Yeon Oh +3 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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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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Cometary Dynamics—Formation and Evolution of the Oort Cloud
AstronomyIn this review, the formation of the Oort Cloud is illuminated from several aspects. One is the history of the subject with an outline of the fundamental discoveries by Öpik, Oort and Hills. It is argued that the basic reason for judging Oort as the real
Hans Rickman
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DYNAMICAL EVOLUTION NEAR-PARABOLIC COMETS TO HALLEY-TYPE ORBITS
Odessa Astronomical Publications, 2017 The capture of comet from the near parabolic flux of the Oort cloud to Halley-type orbits (P < 200 yr, perihelion distanses q < 1,5 AU, and Tisserand parametr T < 2) is investigated Two types of capture into Halley-type orbits are found.
E. E. Biryukov
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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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Were recently reported MHz events planet mass primordial black hole mergers?
European Physical Journal C: Particles and Fields, 2021 A bulk acoustic wave cavity as high frequency gravitational wave antenna has recently detected two rare events at 5.5MHz. Assuming that the detected events are due to gravitational waves, their characteristic strain amplitude lies at about $$h_c\approx 2.
Guillem Domènech
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