A Tour of GJ 176

Narrator (April Jubett, CXC): As astronomers discover more planets outside the Solar System, they are examining what conditions can foster or stifle the habitability of planets. A new study suggests that X-rays emitted by a planet's host star may provide critical clues to just how hospitable a star system could be.

A team of researchers used data from NASA's Chandra X-ray Observatory and ESA's XMM-Newton to look at the X-ray brightness of 24 stars with masses similar to the Sun that were at least a billion years old.

Since stellar X-rays mirror magnetic activity, X-ray observations can tell astronomers about the high-energy environment around the star. In the new study the X-ray data from Chandra and XMM-Newton revealed that stars like the Sun and their less massive cousins calm down surprisingly quickly after a turbulent youth.

This is good news for the future habitability of planets orbiting Sun-like stars, because the amount of harmful X-rays and ultraviolet radiation from stellar flares striking planets in orbit around them would be less than scientists used to think.

Astronomers will continue to look at many factors that they think play into the habitability of planets around the thousands of exoplanets that have been discovered. Studies like these show that X-rays can play a critical role in the ultimate question of where life might exist elsewhere in the Universe.