Memories of past close encounters in extreme trans-Neptunian space: Finding unseen planets using pure random searches
arXiv:2102.02220 · doi:10.1051/0004-6361/202140311
Abstract
Context. The paths followed by the known extreme trans-Neptunian objects (ETNOs) effectively avoid direct gravitational perturbations from the four giant planets, yet their orbital eccentricities are in the range between 0.69-0.97. Solar system dynamics studies show that such high values of the eccentricity can be produced via close encounters or secular perturbations. In both cases, the presence of yet-to-be-discovered trans-Plutonian planets is required. Aims. If the high eccentricities of the known ETNOs are the result of relatively recent close encounters with putative planets, the mutual nodal distances of sizeable groups of ETNOs with their assumed perturber may still be small enough to be identifiable geometrically. In order to confirm or reject this possibility, we used Monte Carlo random search techniques. Methods. Two arbitrary orbits may lead to close encounters when their mutual nodal distance is sufficiently small. We generated billions of random planetary orbits with parameters within the relevant ranges and computed the mutual nodal distances with a set of randomly generated orbits with parameters consistent with those of the known ETNOs and their uncertainties. We monitored which planetary orbits had the maximum number of potential close encounters with synthetic ETNOs and we studied the resulting distributions. Results. We provide narrow ranges for the orbital parameters of putative planets that may have experienced orbit-changing encounters with known ETNOs. Conclusions. Our calculations suggest that more than one perturber is required if scattering is the main source of orbital modification for the known ETNOs. Perturbers might not be located farther than 600 AU and they have to follow moderately eccentric and inclined orbits to be capable of experiencing close encounters with multiple known ETNOs.
12 pages, 5 figures, 3 tables, 5 appendixes. Accepted for publication in Astronomy and Astrophysics Letters. Abstract abridged
References in corpus (12)
- The NumPy array: a structure for efficient numerical computation
- astroquery: An Astronomical Web-Querying Package in Python
- The Planet Nine Hypothesis
- Discovery of a wide planetary-mass companion to the young M3 star GU Psc
- Extreme trans-Neptunian objects and the Kozai mechanism: signalling the presence of trans-Plutonian planets
- Formation of Super-Earth Mass Planets at 125-250 AU from a Solar-type Star
- Long-term orbital dynamics of trans-Neptunian objects
- First detection of orbital motion for HD 106906 b: A wide-separation exoplanet on a Planet Nine-like orbit
- Non-resonant secular dynamics of trans-Neptunian objects perturbed by a distant super-Earth
- OSSOS XV: Probing the Distant Solar System with Observed Scattering TNOs
- Binary stripping as a plausible origin of correlated pairs of extreme trans-Neptunian objects
- Evidence for a possible bimodal distribution of the nodal distances of the extreme trans-Neptunian objects: avoiding a trans-Plutonian planet or just plain bias?