Perspectives on the distribution of orbits of distant Trans-Neptunian objects

Abstract

Looking at the orbits of small bodies with large semimajor axes, we are compelled to see patterns. Some of these patterns are noted as strong indicators of new or hidden processes in the outer Solar System, others are substantially generated by observational biases, and still others may be completely overlooked. We can gain insight into the current and past structure of the outer Solar System through a careful examination of these orbit patterns. In this chapter, we discuss the implications of the observed orbital distribution of distant trans-Neptunian objects (TNOs). We start with some cautions on how observational biases must affect the known set of TNO orbits. Some of these biases are intrinsic to the process of discovering TNOs, while others can be reduced or eliminated through careful observational survey design. We discuss some orbital element correlations that have received considerable attention in the recent literature. We examine the known TNOs in the context of the gravitational processes that the known Solar System induces in orbital distributions. We discuss proposed new elements of the outer Solar System, posited ancient processes, and the types of TNO orbital element distributions that they predict to exist. We conclude with speculation.

OSSOS. XXI. Collision Probabilities in the Edgeworth–Kuiper Belt

“…Therefore a dedicated TNO survey is more suitable and desired for extensive follow-up observations, as well as characterization of the above biases. For a review on the biases associated with KBO observations, see Kavelaars et al (2020).…”

The Scientific Impact of the Vera C. Rubin Observatory’s Legacy Survey of Space and Time (LSST) for Solar System Science

“…Current predictions suggest that the LSST alone could be responsible for a five-fold Completeness for various populations; baseline LSST simulations PHA @H<20.00 PHA @H<22.00 NEO @H<20.00 NEO @H<22.00 MBA @H<18.00 MBA @H<21.00 Trojan @H<16.00 Trojan @H<18.00 TNO @H<6.00 TNO @H<8.00 Figure 1. LSST discovery completeness as a function of time, for various modeled solar system populations (Granvik et al 2018;Grav et al 2011;Petit et al 2011;Kavelaars et al 2009). Cumulative completeness is reported for two different absolute magnitude (H) values; one near the bright end of the population (solid lines) and one near the 50% completeness level (dashed lines).…”

A Lopsided Outer Solar System

“…In a recent paper, , we showed that O(20) Earth masses are required for the instability to occur in a primordial scattered disk between ∼ 10 2 − 10 3 AU in the solar system under the orbit-averaged, gravitational influence of the giant planets. The instability can also generate a gap in perihelion at a few hundred AU, as observed in the outer solar system (Kavelaars et al 2020). The saturation timescale for the instability in a 20 Earth mass disk is 660 Myr, far less than the age of the solar system.…”