A comet from another star system does not arrive every year. That is part of what made 3I/ATLAS so compelling when it ...

Radio silence has long puzzled those searching for extraterrestrial intelligence, but the answer might lie much closer to the source of potential signals than previously thought. Conditions around ...

Astronomers swept millions of candidates and found no alien signals from K2-18b, setting the first power limit on any ...

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 ...

Solar winds and coronal mass ejections may scatter narrow signals, making them harder for Earth-based telescopes to detect. The SETI Institute uses radio telescopes to search for signs of intelligent ...