On the consequences of the existence of planet 9 obtained as a result of simulation

Yu. A. Chernetenko

Transactions of IAA RAS, issue 53, 60–66 (2020)

DOI: 10.32876/ApplAstron.53.60-66

Keywords: planet 9, long-period comets, Sun grazing comets, orbital elements, Oort cloud

Abstract

In Batygin K. E., Brown M. E. “Evidence for a distant giant planet in the solar system”, the authors show that unusual distribution of the orbits of a number of open celestial bodies in the region of the scattered disk can be explained by the gravitational influence of a hypothetical planet 9 with a mass of 5–20 Earth masses moving in elliptical orbit with the following elements relative to the ecliptic plane: Ω = 113º, i = 30º, ω = 150º, e = 0.6, а = 700 AU. In E. Michaely and A. Loeb “Shaping of the inner Oort cloud by Planet Nine”, the authors consider the dynamic interaction of such a planet with the mass of 10 Earth masses and 32,000 zero-mass particles in orbits around the Sun at distances of 700–7000 AU. The simulation was performed by numerical integration over an interval of 4 Gyr. It is found that some particles are dynamically unstable, reach the eccentricities values of e > 0.98, and form long-period comets with values of semi-major axes a = 1100–1500 AU (up to 3000 AU) and Sun grazing comets. The predicted distributions of angular elements for these groups of comets are given. In this paper, distributions of angular elements are obtained for long-period comets with a = 1000–2000 AU (81 comets) and Sun grazing sporadic comets (q < 0.1 AU, e = 1.0) (73 comets). Due to the relatively small number of comets observed, only the distributions of inclinations can be considered to be reliable, and they are rather close to two considered groups of comets. However, these distributions differ significantly from the corresponding distributions predicted in E. Michaely and A. Loeb “Shaping of the inner Oort cloud by Planet Nine”. The possible reasons for these discrepancies are discussed.

Citation