Detective astronomers have discovered at least one unseen alien planet, and possibly another, around a distant star by observing the odd behavior of a planet already known to orbit the same star. The ...

Mars. From forming black holes to phantom dark energy, discover the cosmic mysteries astronomers uncovered last year.

Technosignatures are theoretical signs of technologically advanced alien civilizations, but so far, none of those civilizations have phoned home. Researchers from the Search for ExtraTerrestrial ...