LIGHT SPEED

According to the laws of physics we can never travel faster than the speed of light...or can we? Light speed allows us to see things instantly here on Earth, and shows us the entire history of the universe going back nearly 14 billion years. Learn all about light speed, the ultimate constant in the universe and discover ways scientists envision breaking the "light barrier" which may be the only way the star travel of our imaginations ever comes to reality.

EDGE OF SPACE

Low Earth Orbit, 120 miles above sea level, is where the majority of space exploration has occurred. This 1,100 mile band around Earth is where--for a cool $20 million--any private citizen can take the vacation of his or her life on the International Space Station.

GRAVITY

Gravity is the most powerful and exacting force in the universe. It is pervasive and penetrating. Gravity binds us together, its reach hangs stars in the sky and its grip crushes light. Gravity holds planets together, and leashes them to their suns. Without gravity, stars, comets, moons, nebulae, and even the Earth itself would not exist. Explore how science and humanity discovered, overcame and utilized gravity.

UNEXPLAINED MYSTERIES

Delve into the myths, misconceptions, truths and amazing mysteries of our unique universe. Could life exist on Mars? Is time travel possible and does Einstein's theory of relativity support it? Is there a companion dark star to our sun and could it pose a threat to earth? Learn about the spark that lit the big bang. Take a journey from science fiction that predicted all these things, to the scientific reality of what they mean to us in the ever-changing universe.

MYSTERIES OF THE MOON

For thousands of years, mankind has found comfort in its presence. It's been a lantern for nighttime travelers, a timekeeper for farmers, and a location finder for sailors at sea. For some cultures, it's even been a god. It's the only cosmic body ever visited by human beings. From afar, the Moon's luminance has captivated us since the beginning of time. And a closer look at the beacon in the dark sky reveals an ever-present source of myth, intrigue, controversy and unsolved mysteries.

ALIEN PLANETS

Have planet hunters finally found proof of other Earthlike worlds? Astronomers have now discovered over two hundred alien worlds, beyond our solar system, that were unknown just a decade ago. Discover planets that rage with fiery hurricanes and bizarre planets covered by water so dense that it forms a kind of hot ice. Among these weird worlds, Earth actually seems like the oddball with the right conditions for life.

ALIEN MOONS

Travel from the inner solar system to the Kuiper Belt and explore the moons surrounding the planets of the solar system. Many of these moons that were once unknown are now on the cutting edge of astronomical study. Some burst with volcanic fury another spews icy geysers and others offer the possibility of alien life. Are these strange worlds simply hostile environments unfit for humans or do other possibilities exist?

BEYOND THE BIG BANG

The universe began with a massive expansion, billions and billions of years ago, and it continues to expand with every passing second. The idea that the universe, and man's very existence, began with a "Big Bang" is no longer a topic of debate among most scientists--it is essentially taken as fact.

THE MOON

The moon has comforted man for thousands of years. It's been everything from a god to a compass, and the only cosmic body human beings have ever visited. NASA is planning to build a permanent outpost there. Discover how the moon came to be--if you don't already know, you will be astounded.

SECRETS OF THE SUN

It is a fireball in the sky, a bubbling, boiling, kinetic sphere of white hot plasma, exploding and erupting. Its size is almost unimaginable--one million Earths would fit within its boundaries. In this violence is born almost all the energy that makes existence on Earth possible, yet, its full mysteries are only now beginning to be understood.