Georgia State University
Physics & Astronomy Department
Exoplanets — worlds beyond our Solar System!
They are all the rage these days in astronomy, but how do you know if life could be living on them? If a planet gets too close to its host star, it’ll be burnt to a crisp! But too far away and it will be a totally frozen snowball… a chilling thought for any aliens that haven’t invented blankets yet. However, if the exoplanet is orbiting at just the right distance, then liquid water could exist — and maybe even life! This so-called Goldilocks Zone, otherwise known as the Habitable Zone, is where astronomers are looking for habitable worlds around stars beyond our Solar System.
But wait there’s more! Even if a planet is in the Habitable Zone, the star itself could still be too active and eruptive for life to exist on the planet. Just like the Sun has dark sunspots on its surface and can blast out solar flares, other stars can too. Some are so active that their flares might even hit an orbiting planet and destroy any life there! This activity is illustrated in the stars by Paulina Schuler from Georgia Tech. First, we see a super-active scary monster star with lots of starspots and plasma tendrils — a bad activity level for life! Next is a calm sleepy inactive star — the best activity level for life! Lastly, the happy dancing star with only a few spots and weak tendrils represents a tolerable activity level for life. The astronomy research done by Andrew Couperus at Georgia State University studies this activity to see if we can understand its behavior, allowing us to find exoplanets with the best chances for life to survive.
Disclaimer: It is still uncertain what conditions are optimal for life to exist beyond our Solar System, we don’t fully know yet! The description above offers our best current understanding, but it may turn out to be wrong as we learn more over time — that’s how science works!