Fermi Paradox: Where are the aliens? By Elizabeth Howell published 17 December 21 The universe is incredibly old, incredibly large and teeming with potentially habitable planets. So why haven't we found any sign of aliens yet?
The 'Black Knight' satellite: A hodgepodge of alien conspiracy theories By David Crookes, All About Space magazine published 17 December 21 According to conspiracy theorists, the Black Knight satellite is an alien spacecraft orbiting Earth. Here's what's really going on.
NASA's Perseverance rover finds organic chemicals on Mars By Mike Wall published 16 December 21 Perseverance has identified carbon-containing organic chemicals in some of the rocks it's examined on the floor of Mars' Jezero Crater.
How changing levels of iron shaped the evolution of life on Earth — and why alien hunters should take note By Hal Drakesmith, Jon Wade published 11 December 21 During the development of life on planet Earth over billions of years, iron deficiency may have stimulated evolution.
I'm an astronomer and I think aliens may be out there — but UFO sightings aren't persuasive By Chrisy Impey last updated 10 December 21 If intelligent aliens visit the Earth, it would be one of the most profound events in human history.
The Kardashev scale: Classifying alien civilizations By Meghan Bartels last updated 10 December 21 The Kardashev scale classifies hypothetical alien civilizations by how much energy they use.
Why are we still searching for intelligent alien life? By Paul Sutter last updated 10 December 21 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.
Earth Bloomed Early: A Fermi Paradox Solution? By Ian O'Neill last updated 10 December 21 According to observations by Hubble and Kepler, the universe has only just begun to produce habitable worlds — what does this mean for the evolution of intelligent life?
How would we give aliens directions to Earth? By Joanna Thompson published 3 December 21 Giving aliens directions to Earth might be tricky, but scientists have some ideas for how to do it.
NASA's Perseverance rover on Mars just snagged its newest rock sample (photos) By Mike Wall published 24 November 21 Perseverance just snagged its fourth Red Planet sample, drilling another core from an intriguing rock that it sampled a little over a week ago.
'False fossils' littered across Mars may complicate the search for life on Red Planet By Harry Baker published 23 November 21 Researchers warn that there are dozens of potential false biosignatures on Mars that could hinder the search for alien life.
Is there life at Alpha Centauri? New space telescope to seek out habitable planets around sun's neighboring star By Tereza Pultarova last updated 17 November 21 A new space mission announced today (Nov. 16) will look for habitable planets in the Alpha Centauri system, our closest stellar neighbors.
NASA's Perseverance rover on Mars just collected its 3rd sample of the Red Planet (photos) By Mike Wall published 17 November 21 The car-sized Perseverance rover drilled a core sample on Monday (Nov. 15), filling a titanium tube with Red Planet rock for the third time ever.
New era of 'Great Observatories' may be coming for NASA By Mike Wall published 8 November 21 The four original Great Observatories, which launched between 1990 to 2003, provide a good example to follow.
Astronomers target habitable exoplanets, black holes and inclusivity as top priorities for next decade By Mike Wall published 4 November 21 The newly released astronomy and astrophysics decadal survey flags the discovery and study of habitable exoplanets and the exploration of black holes and neutron stars as two top research priorities.
NASA scientists propose new 'alien life evidence' scale By Elizabeth Howell published 1 November 21 As the search for alien life heats up, scientists may need to step up their reporting game a bit.
SETI: Why extraterrestrial intelligence is more likely to be artificial than biological By Martin Rees published 31 October 21 Is there intelligent life elsewhere in the universe?
UFOs and UAP: History, sightings and mysteries By Mike Wall published 29 October 21 REFERENCE Read on for a brief history of UFO sightings, potential explanations for them, and cultural attitudes toward the phenomenon.
Mysterious radio signal from Proxima Centauri was definitely not aliens By Charles Q. Choi published 26 October 21 Potential evidence of extraterrestrial radio signals from Proxima Centauri, the closest star to Earth, were likely just interference from human technology, researchers say.