Open AccessOn the probability that a comet that has escaped from another solar system will collide with the Earth
Author(s) -
Zheng J. Q.,
Valtonen M. J.
Publication year - 1999
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.1999.02337.x
Subject(s) - physics , comet , solar system , planetary system , stars , interstellar comet , astronomy , astrophysics , astrobiology , celestial mechanics
Stars pass the Sun all the time, and many of these stars may have their own planetary systems and their own `Oort cloud' of comets. We consider a straightforward problem in which the planetary system of the passing star is identical to the planetary system of the Sun, and also the cloud of comets is identical to the Oort cloud of the Solar system. We calculate (1) the rate of loss of comets from this other planetary system, (2) the frequency of passage of other stars at a minimum distance r 0 and at a constant velocity v 0 relative to the Sun, (3) the number and velocity distribution of comets coming from the passing star and impacting our planetary system, and finally (4) the number of cometary collisions with the Earth resulting from this process.