Exoplanet Demographics: Physical and Orbital Properties

TL;DR

This paper reviews the statistical properties and distributions of known exoplanets, highlighting key features and trends that inform our understanding of planet formation, evolution, and diversity in the galaxy.

Contribution

It provides a comprehensive overview of the major features and patterns in exoplanet demographics uncovered by recent surveys, emphasizing their implications for planetary science.

Findings

Identification of the Radius Valley and Neptunian Desert.

Discovery of the Peas in a Pod pattern in planetary systems.

Trends in exoplanet properties with host star parameters.

Abstract

The discovery of over 5700 exoplanets has led to a boom in the field of exoplanet demographics over the past decade. Led by swaths of exoplanet discoveries from NASA's Kepler space mission, astronomers have been conducting statistical studies of the exoplanet population in search of trends in various planetary and host stellar parameters. These investigations are informing our understanding of how planets form and evolve, thus putting our solar system into a galactic context. In this chapter, we review many of the major features uncovered in the distributions of physical and orbital parameters of known exoplanets including the Radius Valley, the Neptunian Desert, the Peas in a Pod pattern, dynamical properties that point toward likely formation/migration mechanisms, as well as trends with host stellar parameters such as the time-evolution of exoplanetary systems and the search for planets within the Habitable Zone. The overarching theme is that exoplanetary systems exhibit an incredible diversity of planet properties and system architectures that do not exist within our own solar system. A promising future awaits the field of exoplanet demographics with increasingly deep investigations planned following the launch of numerous dedicated space telescopes over the coming years and decades.