# Evolution of Long Term Variability in Solar Analogs

## TL;DR

This study investigates the long-term variability of solar analog stars over decades, revealing how stellar activity evolves with age and rotation, and discussing implications for planetary climates and habitability.

## Contribution

It provides a comprehensive analysis of activity evolution in solar analogs using long-term observational data, highlighting differences across stellar ages and rotation rates.

## Key findings

- Young stars exhibit variability amplitudes much higher than the solar cycle.
- Old stars show minimal variability, similar to the modern Sun.
- Stellar activity evolution impacts planetary climate conditions.

## Abstract

Earth is the only planet known to harbor life, therefore we may speculate on how the nature of the Sun-Earth interaction is relevant to life on Earth, and how the behavior of other stars may influence the development of life on their planetary systems. We study the long-term variability of a sample of five solar analog stars using composite chromospheric activity records up to 50 years in length and synoptic visible-band photometry about 20 years long. This sample covers a large range of stellar ages which we use to represent the evolution in activity for solar mass stars. We find that young, fast rotators have an amplitude of variability many times that of the solar cycle, while old, slow rotators have very little variability. We discuss the possible impacts of this variability on young Earth and exoplanet climates.