There are hundreds of billions of planets in our galaxy. Scientists now think hundreds of millions of them have conditions where life could arise. What do scientists think are the best ways of reaching out to them? And why do some...

Since the 1940s, unidentified flying objects have been a part of our nation’s cultural phenomena. But for the U.S. government, UFOs have been a mystery and something the military has been investigating for decades. Amna Nawaz discussed...

Half of the universe is filled with expansionist alien civilizations, and it’s only a matter of time before they’ll reach us. OK, that sounded a little sensationalist. But it’s also the conclusion of a recent astrophysics paper. Let’s...

The SETI Institute's Jill Tarter makes her TED Prize wish: to accelerate our search for cosmic company. Using a growing array of radio telescopes, she and her team listen for patterns that may be a sign of intelligence elsewhere in the...

Legendary ocean researcher Sylvia Earle shares astonishing images of the ocean -- and shocking stats about its rapid decline -- as she makes her TED Prize wish: that we will join her in protecting the vital blue heart of the planet.

The silence of the galaxy and the resulting Fermi Paradox has perplexed us for nearly 50 years. But our most recent surveys of the Milky Way finally allow us to draw scientific conclusions about the depressingly persistent absence of...

Hank talks about astrobiology - the study of and search for life in the universe off Earth. Right now, the field has more questions than answers, but all they all seek to answer that one fundamental query: are we alone in the universe?

Scientists have worked out how likely it is that distant planets can see earth, and we are learning new ways to study the magnetic fields of galaxies.

Aliens! Could humans really be alone in this expansive universe? And if we're not, how come we've never made contact with other intelligent life? Everyone's thought about it; especially members of the scientific community. Join Gabe as...

What can an equation tell us about whether or not we're alone in the universe?

There’s probably life somewhere besides Earth, but all the exoplanets are so far away we may never see their surfaces in detail or intercept a clear radio signal from them. How do we determine if a distant planet has life?

Aliens - Are We Looking in the Wrong Place?

Now that we know planets are common in our galaxy, how would we tell if one holds life? Sure, it will take incredibly powerful telescopes and ambitious new space missions, but what are we looking for? What are we listening for? How do we...

Being the only observable intelligent life in the universe gets lonely sometimes, so it's no wonder we're trying to find something out there to phone home about.

With news of radio signals from distant galaxies, a government agency that wants to investigate extra-terrestrial life, and the 66th anniversary of the Roswell Incident, this week has felt like a '90s science fiction melodrama. Hank's...

The Milky way galaxy is composed of up to 400 billion stars, and at least that many planets. Our star, the sun is one of those billions, about a third to halfway out from the galactic center....

Is it possible that the hundreds of scientists around the world that are looking for intelligent life are on a futile mission to nowhere –because there is actually NO OTHER intelligent species in the entire universe – The...

Do Aliens exist? Are we alone in the universe? Where is everyone? Fermi Paradox and Drake Equation: Where is everyone? You probably already know that there are more stars in the universe than all the...

Learn about the mysterious test site of the United States Military at the Nevada Test Site, from the design of the U-2 spy plane to the SR-71.

Is it aliens? Probably not. Why? Because we don't know almost everything, and finding an explanation that could explain almost anything doesn't recognize that there is a whole lot we don't know. We are so extremely biased toward thinking...

Why don’t we go live on Saturn’s moon Titan? What would it mean if we found life elsewhere? How did life get its start on Earth? NASA’s chief scientist Jim Green and astrobiologist Lindsay Hays discuss these and other audience questions...

The people of Hyrule seem to subscribe to a sophisticated religion that is unlike anything that we see in the real world. What could we learn if we were transported into this world as an anthropologist to study Hylianism?

If astrobiologists find life beyond Earth in the solar system, it will most likely be in the form of tiny organisms called microbes – nothing that would talk to us.

The Fermi Paradox raises the question of why, despite the vast number of potentially habitable planets, we have not yet found evidence of intelligent extraterrestrial life. This video explores possible explanations, including the rarity...