Asteroid Rotation Periods: Statistical Analysis in the Diameter-Spin Distribution

TL;DR

This paper statistically analyzes asteroid rotation periods and diameters, revealing distinct clusters, a stable polynomial trend, and an empirical lower boundary, enhancing understanding of asteroid spin characteristics.

Contribution

It introduces a comprehensive statistical model of asteroid diameter and spin period relationships, identifying key clusters and boundaries with a large dataset.

Findings

Three main asteroid groups identified through clustering.

A third-degree polynomial best models the diameter-period trend.

An empirical lower boundary for asteroid rotation periods established.

Abstract

This study examines the rotational characteristics of asteroids through statistical modeling of the diameter-period relationship. A statistical evaluation of the diameter-period relationship was conducted using a dataset of 34,326 asteroids. Clustering identified three main groups, including a dense cluster below the spin barrier, a population of small, fast-rotating asteroids, and a more diffuse group. Geometric and density-based analyses showed that the densest region consists of objects with diameters from 3 to 10 km and rotation periods between 3 and 9 hours, some of which extend beyond the spin barrier. Polynomial modeling demonstrated that a third-degree fit provides the most stable representation of the overall trend without overfitting. Additionally, an empirical lower boundary was identified and proposed, below which no asteroid was found in either the main sample or the selected targets.