Alien hunters should search for technological life on planets that possess a high oxygen abundance in their atmospheres, according to new research that aims to hone the search for technosignatures ...

"You wouldn't need extra effort to look for these technosignatures, if your telescope is already characterizing the planet for other reasons — and it would be jaw-droppingly amazing to find them." ...

Until someone invents warp drive, the only way we can inspect distant exoplanets is with a powerful telescope. However, even the most capable telescopes can only catch faint glimmers from exoplanets.