Space is big.

You could say it's astronomically large.

And if out there, among all those galaxies and stars and planets, there wasn't some kind

of life, well, that seems like a waste of space.

But then again, if it is full of life, then where is everybody?

Who else shares our universe?

What are they like?

Do they know about us?

A lot of people are trying to answer these questions.

From the UFOologists who dig deep into the events in Roswell.

Roswell has certainly become a household word.

It clearly is synonymous with government cover-up and crashed UFO.

To the military pilots who see strange objects hurtling through the air at supersonic speeds.

A lot of people in the Navy have stories like this going back decades.

So this is a pretty normal occurrence.

See strange things in the sky.

To the radio astronomers, searching for signals from intelligent civilizations.

So we're looking out there to see if we can find any radio signals, any optical signals,

anything that might indicate that would tell us that someone else is using a technology.

And the astrobiologists trying to figure out just what life is.

But it may be that life is something different than that than what we have now.

And you can be searching for a long time for something you don't know what it is.

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