How Radio Astronomy Helps Us See the Invisible Cosmos," astrophysicist Emma Chapman describes the hidden corners of space that only radio waves can reveal — and makes the case for contacting aliens.

Astronomers have been scanning the skies for alien radio signals for decades, but so far they’ve heard nary a peep (with one possible exception). But according to a recent study, that could be because ...

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 ...