Ancient Aliens

Space ships over Los Angeles...

Body snatchers controlling our minds...

E.T.'s making contact.

These and other alien-based scenarios

have been the plotlines of countless

science-fiction movies and television shows.

But what if extraterrestrial beings

came to Earth tomorrow?

Would they signal the birth

of a new age of peace and prosperity,

or trigger a war ofthe worlds?

The day that it's announced we're not alone

is the day that this planet changes forever.

The very structures of government

and the very structures of religion will crumble.

Everybody wants to meet an alien.

But we have to start small.

We have to learn how to walk before we can run.

Millions of people around the world

believe we have been visited in the past

by extraterrestrial beings.

What if it were true?

Did ancient aliens really help to shape our history?

And if so, what might happen when they return?

Throughout human history,

man has gazed up at the stars in awe and with wonder.

Our ancient ancestors charted their movements,

identified constellations

and marked time by creating celestial-based calendars.

The stars also became the source of countless myths and legends.

Many ofthese describe visitors

coming down to Earth from somewhere out there.

Others speak of entire civilizations

existing out in the cosmos.

The ancient Sanskrit writings of India

tell us, for example,

there are 400,000 humanlike species

scattered throughout the cosmos

in different planets, different solar systems,

even different dimensions.

But where are these alien beings?

Did they come to Earth in the past,

as the ancient astronaut theory suggests, and then leave?

If so, will they ever come back?

Today, scientists around the world

have stopped waiting around and are taking steps

to find intelligent extraterrestrial life.

Will technology finally be able to prove

what our ancient ancestors believed thousands ofyears ago?

In 1960, astronomer and physicist Frank Drake

set up an unusual telescope in the hills ofWest Virginia.

The strange device was made

from surplus World War II radar equipment.

But rather than containing a traditional optical lens,

it housed a directional radio antenna.

A few simple calculations showed

that radio telescopes have the power to transmit

and receive across literally interstellar distances.

We're talking many light-years.

So Frank Drake turned a radio telescope

on a couple of nearby stars and tuned in

to see if he could pick up a message from the aliens.

So this was a sort of crazy thing to do.

Drake failed to pick up any sounds that day,

but the science of radio astronomy was born.

Ifwe couldn't see aliens in space,

maybe we could hear them.

The things we've focused on in the past

for searching for extraterrestrial life

is really passively trying to discover signals

on the basis that ifthey were technologically advanced,

they would have some form of electricity like we do,

and all electricity generates radiation.

And it sends out the signals, and hopefully we detect it.

In 1961, Frank Drake and a group of astronomers,

physicists and biologists

formed a privately funded organization called SETI:

the Search for Extra-Terrestrial Intelligence.

Their goal was to focus massive radio telescopes

towards space and listen.

Drake estimated the probability

that intelligent life existed out in the universe

in a formula that became known as the Drake equation.

The Drake equation is like a bridge

between scientists and non-scientists,

because it explains what you would want to know

to give a number about how common alien life could be.

There are multiple factors

within the Drake equation.

Like the fraction of stars that could have planets;

and the fraction ofthose planets that could be habitable;

and the fraction ofthose that might have liquid water;

and how many could have evolved intelligent life?

And then one important factor

is the lifetime ofthose civilizations,

and that is a big unknown.

We only know of one-- that's ourselves.

And how long are we going to be around?

That's to be determined.

Using his equation, Drake estimated

that over 100 million advanced civilizations

could exist in just the Milky Way galaxy.

SETI presupposes

that ifyou've got an alien civilization

capable oftraveling that's developed electronics,

they have a fingerprint.

That fingerprint is a repetitive signal.

A repetitive signal will tell them

that it's notjust noise, junk frequencies out there,

but a real attempt at communicating,

maybe not with us, but with each other.

On August 15, 1977,

astronomer Dr. Jerry Ehman

was working on a SETI project at Ohio State University

when he recorded an intermittent signal

coming from the direction of the constellation Sagittarius.

The signal lasted 72 seconds before being lost.

Ehman believed that it was of extraterrestrial origin.

But despite repeated searches

and increasingly larger telescopes,

the signal has never again been detected.

But what if SETI intercepts a transmission from another world?

What would happen next?

According to SETI's Post-Detection Protocols,

once an extraterrestrial radio signal is confirmed,

news ofthe event should be kept secret

until the authorities have been notified.

The government will then decide

whether or not to try and make contact.

I think all bets are off.

Because here's this message.

It could contain enormously important information

that would transform our society and maybe destabilize it.

What is it going to mean for the future of our civilization?

These are momentous questions.

Today, SETI continues to scan

the vicinities of nearby stars

for artificially produced signals

using several ofthe world's largest telescopes.

In the next several years,

when it becomes fully operational,

SETI's new Allen Telescope Array

will allow for the reconnaissance

of up to a million stars.

SETI has to search a huge, huge area.

They'll tell you that now,

they have searched the equivalent of, like,

a glass ofwater compared to the entire ocean on Earth.

They have a long way to go.

While SETI listens passively

to signals from outer space,

NASA has attempted to contact alien life directly,

through messages sent aboard its space probes.

It's a long shot,

but there's no reason, in my mind,

not to expect that life evolved elsewhere.

What's harder to predict, or try and understand,

is how likely is it that it happened close enough

that there'd be someone we could actually communicate with.

In 1972, NASA agreed to attach small plaques

onto the outside of its twin Pioneer space probes,

the first human-built objects

destined to leave our solar system.

NASA contacted Cornell University professor,

Dr. Carl Sagan, to craft the message.

Carl Sagan was one ofthe most active astronomers

in the search for life outside our planet.

He was a very prominent scientist,

he was an excellent astronomer, and he really did a lot

to help us understand how we might contact other life

or detect life elsewhere in the universe.

Sagan, along with SETI founder Frank Drake,

designed a gold-anodized aluminum plaque,

measuring roughly six by nine inches,

that contained a collection of symbolic images

representing humans and Earth.

The man and the woman were nude,

and the gentleman was holding one arm up like this

in what was intended to be

a sign of, uh... a sign of greeting.

A schematic design ofthe solar system

was also shown, with the planned trajectory

ofthe Pioneer spacecraft marked on it,

and a diagram of 14 pulsar stars around the sun

made a chart that might help someone work out

where the craft originated.

We tried to give them an idea ofwhere we're located--

and that's an interesting problem, is to figure out

how you would tell someone where you're located in space,

'cause you don't know where they're going to find it.

And it was all in a very stylistic design,

but in an attempt to hopefully communicate

at least some ofthese ideas.

Five years later, in 1977,

Dr. Sagan got a second chance

at designing an interstellar message

when NASA agreed to attach another one

to the Voyager space probes.

This time, Sagan created a record album

made of gold-plated copper,