Extraterrestrial life

The search for life as we don't know it

Illustration of a small spotlight lighting an empty area, a small alien is off to the side of the light.
Illustration: Aïda Amer/Axios

The most comprehensive search for signs of intelligent life elsewhere in the universe has come up short so far, despite generating more than 1 petabyte of data. But such efforts are just getting started.

The big picture: The project — known as Breakthrough Listen — observed more than 1,300 relatively nearby stars over the course of 3 years, listening for any signs of radio waves that would signal the presence of technologically advanced aliens.

How to tell if an exoplanet is habitable

 An exoplanet (the red spot) orbiting the brown dwarf
This composite image shows an exoplanet (the red spot) orbiting the brown dwarf 2M1207. This is the first exoplanet directly imaged. Image: ESO/Chauvin et al.

Figuring out whether a planet is habitable will take more than just understanding its orbit. According to a new study in the journal Science, scientists will also need to study a world’s atmosphere, magnetic field and even geological composition in order to really know if it’s capable of hosting life.

The big picture: Researchers have been hunting for habitable exoplanets using space and ground-based telescopes for years, but assessing whether a world can support life or not is difficult.