How Sedna and family were captured in a close encounter with a solar sibling
| Autor: | Michael Hammer, Lucie Jílková, Simon Portegies Zwart, Tjibaria Pijloo |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2015 |
| Předmět: |
Solar System
Planetesimal Astronomy open clusters and associations Population FOS: Physical sciences Astrophysics Close encounter minor planets asteroids: general 2012 VP113 education asteroids: individual: Sedna planetary systems Earth and Planetary Astrophysics (astro-ph.EP) Physics Orbital elements education.field_of_study Ecliptic Astronomy and Astrophysics celestial mechanics Planetary system minor planets asteroids: individual: Sedna 2012 VP113 asteroids: general Space and Planetary Science Asteroid minor planets ComputingMethodologies_DOCUMENTANDTEXTPROCESSING Astrophysics - Earth and Planetary Astrophysics |
| Zdroj: | Monthly Notices of the Royal Astronomical Society, 453(3), 3157-3162 Monthly Notices of the Royal Astronomical Society, 453, 3157-3162 Monthly Notices of the Royal Astronomical Society, 453, 3, pp. 3157-3162 |
| ISSN: | 0035-8711 |
| Popis: | The discovery of 2012VP113 initiated the debate on the origin of the Sedna family of planetesimals in orbit around the Sun. Sednitos roam the outer regions of the Solar System between the Egeworth--Kuiper belt and the Oort cloud, in extraordinary wide (a>150au) orbits with a large perihelion distance of q>30au compared to the Earth's (a=1au and eccentricity e=(1-q/a) ~ 0.0167 or q=1au). This population is composed of a dozen objects, which we consider a family because they have similar perihelion distance and inclination with respect to the ecliptic i=10--30deg. They also have similar argument of perihelion omega=340+/-55deg. There is no ready explanation for their origin. Here we show that these orbital parameters are typical for a captured population from the planetesimal disk of another star.Assuming the orbital elements of Sednitos have not changed since they acquired their orbits, we reconstruct the encounter that led to their capture. We conclude that they might have been captured in a near miss with a 1.8MSun star that impacted the Sun at ~340au at an inclination with respect to the ecliptic of 17--34deg with a relative velocity at infinity of ~4.3km/s. We predict that the Sednitos-region is populated by 930 planetesimals and the inner Oort cloud acquired ~440 planetesimals through the same encounter. Accepted for publication in MNRAS; 7 pages, 2 figures, 1 table; extended discussion, corrected typos and references |
| Databáze: | OpenAIRE |
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