Humans have been looking up at the stars for millennia, studying them and dreaming of reaching them.

In the last century, we finally developed the technology to realize those dreams.

Sputnik, the first satellite, launched into space in 1957.

Just a few years later in 1965, astronauts entered the vacuum of space on the first ever spacewalks.

This is astronaut Ed White floating outside of the Gemini 4 spacecraft.

Okay, I'm depreding in the spacecraft.

Okay, you've been the spacecraft.

You look beautiful.

That's just like a million dollars.

And that same decade...

Roger, we copy and pretty good little job.

That's one small step for man.

Neil Armstrong left the first set of footprints on the moon.

If I can see the footprints of my boots and the treads in the fine sandy particles.

And as technology has advanced, we have sent satellites on interstellar missions.

Well, Asia 1 was the fastest spacecraft ever launched

32,481 miles an hour, searched for other solar systems.

Planet hunters have found somewhere around 100 planets outside our solar system and rigged up rovers to map

distant planets.

We even know what it sounds like on Mars. And though technology has changed, one thing has been constant throughout human history,

our fascination with the stars and our attempts to understand how it all works. Consider this, tomorrow millions of people will

look up as a total solar eclipse traces an arc across North America. It's one of

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