Sol: Destroyer of Worlds

An Evolving Star

Sol, the Sun, our closest stellar neighbor, is living a life much the same as any G-type main-sequence star. These stars, unlike the enormous giants and supergiants, have long life spans and relatively stable outputs. Such conditions have been conducive to stable planetary climates, and thus life on Earth has had ideal conditions in which to develop.

Just because the Sun is stable compared to other types of stars does not mean that it remains entirely stagnant. Over the course of its history, the Sun's luminosity, or light output, has increased by about 10% every 1.1 billion years. This evolution created the faint young sun paradox, in which observations of liquid water on early Earth were seemingly incompatible with a solar energy input equal to only 70% of modern values. If we instead look into the future, we quickly reach the conclusion that increase solar output will eventually throw Earth's climate system out of its stable life-supporting balance. Of course, the big question is when.

The sun will continue to gradually warm and eventually become a red giant.

This website designed by Brian Vanderwende, 2012.