What Can the Cosmic Microwave Background Tell Us About the Outer Solar System?

TL;DR

This paper introduces two novel methods using CMB observations to constrain the properties of small objects in the Kuiper Belt and Oort Cloud, enhancing our understanding of the outer Solar System.

Contribution

It proposes new observational techniques leveraging CMB spectral distortions and orbital motion effects to map and analyze Trans-Neptunian Objects.

Findings

Applied the spectral distortion technique to COBE/FIRAS data.

Estimated future CMB experiments' capability to map outer Solar System mass distribution.

Demonstrated potential to constrain TNO properties through CMB observations.

Abstract

We discuss two new observational techniques that use observations of the Cosmic Microwave Background (CMB) to place constraints upon the mass, distance, and size distribution of small objects in the Kuiper Belt and inner Oort Cloud, collectively known as Trans-Neptunian Objects (TNOs). The first new technique considers the spectral distortion of the isotropic, or monopole, CMB by TNOs that have been heated by solar radiation to temperatures above that of the CMB. We apply this technique to the spectral measurements of the CMB by the Far Infrared Absolute Spectrophotometer (FIRAS) on the Cosmic Background Explorer (COBE). The second technique utilizes the change in amplitude of the TNO signal due to the orbital motion of the observer to separate the TNO signal from the invariant extra-galactic CMB and construct a map of the mass distribution in the outer Solar System. We estimate the ability of future CMB experiments to create such a map.