Time marches on except in astrophysics. Einstein taught us that time is a coordinate in space, and it's all relative. Learn about the weird physics of our universe that could make time travel possible. Standing in for Lynne Koplitz this week is J. Richard Gott, author of Time Travel in Einstein's Universe.

The Star Trek TV and movie series imagine a bright future for humans in space, one in which we explore alien worlds with the aid of advanced technology. Because the writers tried to include as much realistic science as possible within the fictional framework, the stories have been an inspiration for students, scientists, inventors, and anyone interested in pondering our destiny on Earth and beyond. In this show, Brandon Fibbs reviews a Star Trek movie, and Lawrence Krauss talks about how Star Trek uses science to explore what is possible in our universe.

Scientists have been searching for aliens in our solar system and beyond, but have not yet found evidence that life exists beyond Earth. SETI, the Search for Extraterrestrial Intelligence, has been scanning the stars for alien radio beacons for 50 years. Radio and TV broadcasts have been leaking from Earth’s atmosphere for over a century, and these traveling time capsules could eventually reach a broader audience than ever imagined. Neil and Lynne review the methods used to locate aliens and discuss what to do if you’re ever abducted.

What's so funny about space and science? Our season finale features the incomparable comedian Joan Rivers. In this episode, she provides color commentary for a Red Carpet parade of previous show topics, including space tourism, the anniversary of Apollo 11, and the search for alien life (both in space and in Hollywood).

Mark Twain said, “Get your facts first, then you can distort them as you please.” Pseudoscience adheres to this adage, but are their distortions deliberate, the result of scientific ignorance, or due to a deep desire for extraordinary possibilities? In our quest to understand the universe, how can we be sure our conclusions are correct? Human beings have evolved to find meaningful patterns in nature, but sometimes the patterns we see are just figments of our imagination — or perhaps the result of wishful thinking.