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Star Passages through the Oort Cloud
Earth, Moon, and Planets, 1996Stars passing through the Oort cloud eject comets to interstellar space and initiate showers of comets into the planetary region. Monte Carlo simulations of such passages are performed on a representative distribution of cometary orbits. Ejected comets generally lie along a narrow tunnel “drilled” by the star through the cloud.
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Estimates of Mass and Angular Momentum in the Oort Cloud
Science, 1988Estimates can be made of unseen mass (in the form of cometary nuclei) at the heliocentric distances between 3 × 10 3 and 2 × 10 4 astronomical units (AU) under the assumptions (i) that the Oort cloud is a rarefied halo surrounding the core (dense, inner cometary cloud) and (ii) that the mass ...
L S, Marochnik +2 more
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The angular momentum of the Oort cloud
Icarus, 1991An evaluation is made of the work of Marochnik et al. (1988), which estimated that the angular momentum of the Oort cloud is 2-3 orders of magnitude greater than the planetary system's total angular momentum. It is noted that most of the angular momentum in the currently observed Oort cloud is the result of the effects of external perturbers over the ...
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A hypothesis on the Oort clouds of planets
Earth, Moon, and Planets, 1991Although, we have no quantitative arguments to prove, but we have good reasoning to believe that the Oort clouds existed surrounding the planets. The short period comets, Apollo-Amor-Toro-asteroids and such other objects may be the relics of the Oort clouds that had existed surrounding the planets long ago.
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Origin of oort cloud comets in the interstellar space
Celestial Mechanics and Dynamical Astronomy, 1992Comets must form a major part of the interstellar medium. The solar system provides a flux of comets into the interstellar space and there is no reason to suspect that many other stars and their surrounding cometary systems would not make a similar contribution.
Mauri J. Valtonen +2 more
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Some comments on the Oort cloud
Astrophysics and Space Science, 1977The arguments used by Lyttleton to prove the nonexistence of the Oort cloud are reviewed, and it is shown that Oort's hypothesis remains consistent with observation. The 1950 model of the cloud cannot be correct and, by use of the results from a number of more recent papers, an ‘improved’ model is described and compared with observations.
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The evolution of comets in the Oort cloud and Kuiper belt
Nature, 2003Comets are remnants from the time when the outer planets formed, approximately 4-4.5 billion years ago. They have been in storage since then in the Oort cloud and Kuiper belt-distant regions that are so cold and sparsely populated that it was long thought that comets approaching the Sun were pristine samples from the time of Solar System formation.
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Oort Cloud Ecology - II. The Chronology of the Formation of the Oort Cloud
Astronomy and Astrophysics, 2021Simon Portegies Zwart +2 more
exaly
Interstellar Objects Outnumber Solar System Objects in the Oort Cloud
Monthly Notices of the Royal Astronomical Society: Letters, 2021Amir Siraj, Abraham Loeb
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Oort Cloud Ecology - I. Extra-Solar Oort Clouds and the Origin of Asteroidal Interlopers
Astronomy and Astrophysics, 2021Simon Portegies Zwart
exaly