A mysterious radio signal detected nearly five decades ago and long speculated to be evidence of extraterrestrial life may finally have a natural explanation, according to new research. The so-called ...

Researchers are zeroing in on more deliberate “narrow-band” alien signals, well outside the radio frequencies SETI has ...

The first unmistakable signal from another intelligence may not be a cheerful greeting. A growing group of researchers is arguing that our inaugural contact is more likely to be a distress call, the ...

Most alien-signal searches listen to a narrow part of the radio spectrum, but astronomers are now testing higher frequencies that have barely been explored. A first search using archived ALMA ...

On August 15, 1977, the Big Ear Radio Telescope in Delaware, Ohio, received the most powerful signal it would ever detect during its decades of observations. The signal lasted just 72 seconds, but ...

Astronomers might be hunting for alien signals in all the wrong places. A new ...

Astronomers may have been listening for alien civilizations in only a small slice of the radio spectrum while overlooking a largely unexplored range of higher frequencies. Using archived data from the ...

If advanced aliens lived on a planet within a few hundred to a thousand light years away from Earth, then vast numbers of their signals must already have crossed Earth without being noticed, a new ...

A comet from another star system does not arrive every year. That is part of what made 3I/ATLAS so compelling when it appeared in July 2025. It streaked into the Solar System on a path so extreme that ...

The search for extraterrestrial intelligence (SETI) has yet to detect alien technosignatures like radio waves, but the cosmos is vast, and there are plenty of places left to look. New research ...

Astronomers searching for signs of extraterrestrial intelligence may have been missing alien signals in part of the radio spectrum that has not recently been explored.