According to conspiracy theorists, the Black Knight satellite is an alien spacecraft orbiting Earth. Here's what's really going on.
UFOs, or Unidentified Flying Objects, and extraterrestrials are perennial favorites in science fiction, but to date there have been no confirmed encounters on Earth. Still, strange sights in the night sky have been attributed to UFOs or aliens over the decades, most famously in Roswell, New Mexico, where many believers claim an alien craft crashed on a farm in 1947. In 2017, the existence of a secret U.S. government program that tracked "UFO" sightings by military pilots, which shut down in 2012, was brought to light in a New York Times report.
Scientists warn that increased space exploration raises the risk that alien organisms will invade Earth and that Earth organisms will invade other planets.
A photographer in Zurich, Switzerland, spotted the glowing object while four SpaceX astronauts returned to Earth thousands of miles away.
Humans have scanned and searched the heavens for signs of other advanced civilizations in the universe. And we've found nothing. Absolutely nothing. Maybe we shouldn't focus on intelligent life.
REFERENCE Read on for a brief history of UFO sightings, potential explanations for them, and cultural attitudes toward the phenomenon.
Potential evidence of extraterrestrial radio signals from Proxima Centauri, the closest star to Earth, were likely just interference from human technology, researchers say.
UFO enthusiasts who rallied in 2019 to invade Area 51 may have been joking about "storming" the base. But law enforcement officials took the idea very, very seriously.
The water flowing from a medieval fountain in the Italian village of Fontecchio bubbles with extraterrestrial effervescence.
The creepy alien abduction horror game "They Are Here: Alien Abduction Horror" is coming in 2022 and there's a free-to-play demo available now.
Researchers show how intelligent aliens might draw nearly-limitless power from a black hole using a Dyson sphere.
Space.com recently caught up with author and journalist Leslie Kean to discuss UFOs and where research into the puzzling objects is heading.
Two aircrafts flying over Canada reported a "bright green UFO" that disappeared into the clouds on July 30.
People have described extraterrestrial encounters that take place in a dreamlike state, and experiments suggest that such experiences may be lucid dreams.