Space captains must figure out how to reach an abandoned alien space station before any other species in the galaxy. The problem? Where to store caches of fuel along the way. Viewers needn't be aliens to figure out this riddle.

Is it possible to contaminate the planets our astronauts or rovers visit? With current technology, it is impossible to send a completely sterile rover to Mars, and there could be up to 30,000 different microbes on the space traveler!...

Are aliens real? Find out with an engaging video that details the three ingredients—water, oxygen, and food—necessary for living things to survive. 

Is there life beyond Earth? Take a look through a virtual telescope in a video that provides possible scenarios in which life could exist on other planets.

Listen to top theoretical physicists, such as Steven Hawking, as they describe, define, and consider intelligent life on extra-solar planets. Many interesting questions are raised in this theoretical clip. Entice your class to think like...

Examine pulsars, what they are, and what life would be like on a planet near a pulsar. Part four describes proto-planets, primordial planets, young stars, gravitational pull, and what life could be like for extra-solar worlds.

The final part in the series, it concludes the story of life on extra-solar planets. Scientists examine the water on Earth, the moon Europa, and super Earths made only of water, found in extra-solar systems. Learn about alien chemistry,...

Olivier Guyon, professor of optical science and astronomy, explains how scientists are searching for other planets that can support life. Viewers learn the odds of finding a habitable planet, how long it would take, and some techniques...

James Cameron rocketed onto the action film scene with 1984's "The Terminator" and followed that up with a highly anticipated sequel to the 1979 film, "Alien." His film, "Aliens," would go on to not only be a financial success, but a...

Watch this video to learn PBS NOVA: how scientists calculate the probability of intelligent life forms on other planets. Listen to experts' opinions on this topic and learn what scientists are doing to search for extraterrestrials. [51:58]

Learn how scientists detect life on other planets, then test yourself to see if you can do it. A teachers' link at the top leads you to ideas for discussion and investigation. (Note: Some videos may no longer load.)

A video series where astrophysicist Matt O'Dowd investigates the outer reaches of space. Explores topics from asteroids to gravitation waves to sci-fi!

A video discussing the reasons why we haven't detected any other civilizations yet. [5:09]