Are we alone in the universe? Consider mysterious "extraterrestrial" radio signals. Unexplained gases on other planets.

Australia's space agency said there's a completely rational, albeit cosmic, explanation behind the mysterious orbs that ...

Eventually, we'll launch a mission dedicated solely to studying an interstellar object. When that day comes, which one should ...

Each question in the ABC 50/50 quiz has only two options: one is right; the other is wrong. But there's a catch.

Take a drive to the CIA’s Area 51 – a route with more UFO sightings and unexplained mysteries than anywhere else on Earth ...

NASA’s Viking 1 lander set down in the Chryse Planitia region of Mars. Its identical twin, Viking 2, followed on Sept. 3 of ...

Steven Spielberg’s credulity makes his latest alien contact film, Disclosure Day, mawkish and old-fashioned rather than ...

The makers of the blockbusting sci-fi thriller reveal how they made a hit, why Kevin Spacey was almost involved and what went wrong with the sequel ...

Got a nasty stomach bug that won’t go away? It could be cyclosporiasis, a parasitic infection that causes weeks of ...

Teetering near endangered status, the starlet sea anemone produces “an ancient mechanism” for fighting viruses that ...

Does anywhere in the country better represent this era of the American experiment than a self-governing tech-company town ...

Military history is much more than battlefield trivia. Stacker took a look at 25 recent "Jeopardy!" questions about the ...