Transcriber: Amanda Chu

So I'm four years old.

It's the early 1960s.

And I'm looking at a globe of the Earth,

and I can clearly see

that Africa and South America fit together.

It's like a picture puzzle with only two pieces,

or a broken cookie.

Obviously, they had to have fit together

once upon a time.

Of course I wasn't the first person to notice that.

Mapmakers and others

had been seeing it for hundreds of years.

But if I had brought my observations

to a mainstream geologist of the early 1960s,

they would have told me that it was just a coincidence,

for there was no way known to science

that something as substantial as a continent

could possibly move around on the Earth.

That was just crazy talk.

But jump forward to the end of the '60s.

Hard-working scientists on both sides of the Atlantic

and searching the deep-sea trench in the middle

had found the evidence,

and developed the understanding

of how in fact the lighter continental material

could move around on the heavier material below,

and the science of plate tectonics

is now a key part of how we understand our world.

So this just shows how science changes -

sometimes in one childhood,

other times over decades and years, slowly and painfully.

Now, jump ahead - fast-forward to about 10 years ago.

Now I've got the internet,

where any burning question can be answered with a quick search.

And I'm looking at a website with some scientific content,

but it's on the fringe of science.

It calls into question some of the commonly accepted science.

Now, I'm not going to tell you what the website is just yet,

because it's in that Twilight Zone

where respectable scientists don't go.

But we'll get there eventually,

so trust me.

But the question that this website brings to my mind is this:

Is it possible to orbit the Earth

in a way that creates a single, circular ground path

on the ground below?

Like, if I took a rubber band and stretched it around the globe,

could my satellite go around and just stay over that band all the time?

Now, this is not an easy thing to explain.

But I do an internet search,

and I can't find an answer.

And I go to a friend who is a genuine rocket scientist,

and I put it to him,

and he thinks for a moment, he goes,

“Sure! Orbit over the equator!”

Okay, yeah, that's a valid answer.

If I'm going over the equator and the Earth is turning,

it doesn't matter what speed anyone's going,

I'm always going to stay right over the equator.

But I want my rubber band at other angles.

I need to have that.

And for that, he can't give me an answer,

and I can't find a clear answer on the internet.

How strange is that?

Well, here's an image

that will help begin to understand why this is a hard problem.

We're all familiar with this. We're citizens of the Space Age.

The International Space Station, NASA Mission Control,

we go over a path again and again.

It's like wrapping a ball of string.

The International Space Station circles every 90 minutes,

the Earth turns every 24 hours -

you get this kind of pattern.

Alright.

So, what am I going to have to learn to figure that out?

Well, we have to go a little bit deeper.

I promise, no math.

But there are three key things you need to know about Earth orbits

that will inform the ground path you make below.

First thing is your altitude.

The ISS orbits around 400 km above the Earth.

On this globe, that's like a quarter of an inch,

seven millimeters, above the globe.

The second thing is the inclination of your orbit to the equator.

The ISS is at 51 degrees,

meaning it goes over most of the land surface of the Earth, eventually,

as it goes around and around.

The third thing is the shape of your orbit.

Now, the shape can be anything from round,

like the ISS,

out to very, very elliptical,

long and narrow.

But the key thing about an ellipse is that the center of the Earth

has to be at one of the focus points of the ellipse.

And this is where the math gets tricky, okay?

Thanks to Johannes Kepler in the 1600s,

we can calculate exactly your speed and position on that ellipse

for any given shape.

Alright. Now we've got all this loaded up.

The altitude, the inclination, the shape of the ellipse, the speed -

my brain is whirling.

How am I ever going to find an answer?

And if there's not an answer,

how am I going to prove that to myself too,

to know that my quest is fruitless.

Okay ...

So I get on the phone to a friend

who's a genuine aerospace mathematician guy,

and he points out

that there's only a certain number of categories of Earth orbits.

So I start looking through these categories,

and there's two of them that jump out at me

as really interesting.

The first one is Geostationary, right?

Geostationary: this is an orbit that has a circular shape,

an inclination that puts it out about here -

way far from the Earth.

And the key thing is that its altitude makes it go around the Earth

in the same time it takes the Earth to turn!

This means you stay over the same spot all the time,

and this makes it easy

for the television satellite dish installer

to come to your house and point it at one spot in the sky

because the satellite is always right there.

Even at night when the stars and the moon are sliding past,

the satellite is right there.

But now the weird thing is

the satellite has a ground path that's not a rubber band at all.

It's a single dot!

So in a way, this is like the opposite of what I'm looking for, right?

The second orbit that looked really interesting is called "molniya."

"Molniya" is the Russian word for "lightning."

This was developed by the Soviet Union in the early days of the Space Age.

The molniya orbit is highly inclined,

and very elongated.

And it's timed

so that it goes around the Earth in exactly half a day.

And that gives it this amazing U-shape,

the double-U shape,

that goes around the Earth.

The molina satellite hangs out high over one side of the world,

say North America -

and perhaps it's taking pictures or listening to radio -

then it comes zipping in around the Earth

and comes back out,

and then hangs out again,

but half a day has gone by,

so now it's over the other side of the planet,

and it can download what it learned on the other side.

So these two orbits give me an idea.

What if I was in an orbit

that took exactly two days to go around the Earth?

Okay? So I'd start out above the Earth at some arbitrary point.

One day later, I'm on the other side.

And one day's gone by, the Earth has turned completely,

so I'm also over the opposite side of the Earth from where I started.

Another day goes by, I’m back to where I started in my orbit,

the Earth has turned again, I'm back over the same spot!

That seems promising, right?

I'm getting really obsessed with this search!

I get on the phone to the friend who's the aerospace mathematician guy,

and he's really like,

“Okay! Crazy quest. Good. Good luck with that!"

"Tell you what. There's a really great website called 'STK.'

You should go check it out

because it will show you any orbit you want.”

Okay, I go to STK, I do my basic calculations,

I put in my numbers, and I push the button.

And there it is right before my eyes!

A single ground-path, circular Earth orbit!

I'm stunned that it was actually there!

Now I'm thinking,

"I can't be the first person to notice this!

I'm not a rocket scientist."

So I get on the phone to another friend

who works for big aerospace companies designing Earth orbit missions.

And he sounds a little bit skeptical,

but he fires up his copy of STK.

He asks for my numbers, he puts them in,

and boom! - he gets the same result!

And he says: "You know, I've never seen this before.

You should write this up.

Put it in an aerospace journal."

Okay. Cool.

Well, so it's a new thing, right?

And new things need names,

so I'm thinking the key property of this

is that it's a two-day orbit,

so I'm going to call it a "Two-day Orbit,"

or "2DO" for short,

to fit the pattern of all the other three-letter acronyms

that aerospace people like to use.

(Laughter)

So now that I've got a name for it, I want to get back to my original quest.

But for a brain like mine, and maybe like yours,

you immediately think, "What about a three-day orbit?

Or a four-day orbit? What're their ground paths like?"

And yeah, it's all there, it's really interesting! I had to look!

So I go back to my original search.

And I'm fine-tuning the orbit -

a 31-degree inclination, set over a certain point on the Earth.

And I find it has a number of really interesting and unusual properties.

One: The orbit stays outside of the Van Allen Belts,

the radiation belts that are out around here around the Earth.

And if you're an astronaut, you don't want to hang out in there,

you can fly through it.

If you are electronics, you don't want to be in there either.

So this orbit is outside of that.

Second feature:

It's also outside of the Earth's magnetic field all the time,

so the magnetic field is inside of you.

Third feature:

It's always in the sun!

It's an orbit that never crosses into the Earth's shadow that's streaming away,

even at the northern solstice -

the most extreme tilt of the Northern Hemisphere.

So, what do we do with an orbit like this?

Well, since we're always in the sun,

how about make a super power satellite

where we can collect solar energy

and beam it down to a series of sites on the ground below, giving them power,

charging them up every two days as we come back around?

Or maybe we could put up a whole series of mirrors dancing around,

and we could shine light down onto the Earth,

into dark places that need more light.

Or maybe there's other uses.

All right ...

But what about that website that got this all started?

That fringe one

that respectable scientists may not want to venture into?

Well, it was this.

A researcher named Jim Alison noticed

that a significant number of ancient sites around the world -

some of the oldest, most mysterious structures -

all line up on a single circle around the Earth -

a straight line.

When you put a two-day orbit over this exact path,

it's not an exact circle,

it's got slightly a potato-chip shape to it,

but it lines up pretty closely.

Let's hop aboard a Two-day Orbit satellite

and take a tour of all these ancient sites.

We start over the most famous megalithic site -

the Great Pyramids,

with their mysterious chambers, hidden tunnels, and of course the Sphinx.

A little bit later, we cross the Sahara,

we cross the Atlantic Ocean,

we cross over the Amazon basin,

and we come to Machu Picchu,

with its mysterious stone structures and Ollantaytambo

and all the other ancient sites around Cusco.

Then we fly past the Plain of Nazca,

with its mysterious etched drawings on the floor of the desert.

Of course we're 60,000 kilometers up,

so if we want to see those shapes

we’ve got to have a pretty good telescope.

We keep going, across the Pacific.

4,000 km - we cross directly over Easter Island,

with its gigantic heads, the "moai" figures -

actually they're full figures that are buried down into the ground.

Continuing on across the Pacific,

we come back up over the equator.

We fly up over Cambodia

and the ancient temples of Preah Vihear and Angkor Wat.

Continuing on up into Asia, we fly over India to Pakistan,

to the site of Mohenjo-daro,

one of the oldest Western civilization locations,

with its script that has still not been decoded,

because it's so old and remote from us.

We continue on over the Middle East,

past Persepolis, and the great buildings at Ur.

And then we continue on over Petra,

with its amazing stone structures, dug into the walls.

And then it brings us back to the Great Pyramids,

right where we started.

So obviously, not all ancient sites are on this circle.

Stonehenge, the Wailing Wall in Jerusalem,

all sorts of sites in China, Africa, Asia,

Central America.

But the sites that are on the circle

have a lot of things in common.

One:

They have some of the largest stonework humans have ever done,

huge blocks that we wouldn't realistically try to move today.

Two:

The style of the stonework is precisely cut.

They fit together. You cannot fit a knife blade in between some of these rocks.

And then look at Easter Island in specific.

The big moai figures get most of the attention -

there's hundreds of them.

But there are also walls,

walls that appear to be some of the oldest things

on Easter Island made by humans.

The walls are made of basalt - an extremely hard stone.

They match the style of construction at Machu Picchu,

4,000 km away across the Pacific,

also made of basalt.

Then there is these mysterious knobs and scoops:

Many on the pyramids; other, Egyptian sites;

many all over South America.

What are those knobs for? How were they made?

Why did they go to the effort of putting that in?

We don't know!

The scooping, it looks like it was mashed potatoes

and somebody came along with a trowel and just scooped out the rock.

We don't know!

Then there is the precision stonework -

perfectly flat surfaces!

Things that you would take to a machine shop

and they would grind with diamond.

We can't figure out how this could have been done

with bronze or iron tools.

OK. Want to get a little bit weirder?

There are cultures around the world that have the "bird man," the "fish man."

Asia's got them. South America’s got them.

And they have this other feature: the handbag.

"The handbag of the gods."

(Laughter)

Why? How? All around the world.

The handbag of the gods is also found in India, in Indonesia,

and most recently, at Gobekli Tepe in Turkey,

which has been buried for 10,000 years at least.

Which means the handbag has been around for at least that time.

It wasn't added by people later on.

Okay. Now I'm not here to invoke ancient astronauts or space aliens.

To me that doesn't answer anything.

It's like putting a bumper sticker on it,

but I want to read the book!

Where did all this come from?

Who created this?

I don't want to take anything away

from the ancient peoples who did this work.

I want to know more about them.

I want to know how they did it, when they did it,

and I want to give them full credit for their great work!

So what we do?

Well, we get out our science toolkit.

First thing: What's our theory?

Well, researchers who look into this

question our traditional story of the ancient human past,

where we go from a long period of hunter-gatherers

up to settling down and doing agriculture,

and eventually moving into city-states.

Researchers suspect -

and there is good evidence for -

13,000 years ago there was a more advanced form of human civilization.

How advanced is hard to say,

but we know they could do stuff with stone that we really cannot.

And then what happened?

Suddenly there was a catastrophe!

Something terrible happened -

the oceans rose, temperatures dropped, populations were wiped out,

cities were abandoned.

Time goes by;

civilization recovers.

We get into hunter-gatherer mode.

We get into agriculture, city-states.

Okay. So it's a story, right?

Is it a good story? Maybe. Maybe not.

But what does the science tell us?

Well, to begin with,

we have great data showing the oceans were 100 meters lower 15,000 years ago.

100 meters! 330 feet!

That means the ancient coastlines and islands

are now completely submerged.

Secondly: Greenland ice cores and Mid-Atlantic sediment samples

show us that there was a sudden drop in temperature,

and it lasted for a thousand years or so,

around the world.

Thirdly: The male DNA has clues.

Around the world the diversity of the male DNA drops precipitously,

again, around 13,000 years ago.

It wasn't just here or there, it was around the world.

A lot of men were not passing on their DNA to future generations.

That declined,

and then it began to recover.

So what could have happened that could explain all of these things?

Well, we have evidence that something hit North America -

a comet or a meteorite.

It left very distinctive particles all over the hemisphere.

It set a lot of stuff on fire

because there's very distinctive soot and ash particles

found right there as well.

We have seen half a million impact craters,

ranging from New Jersey all the way down to Alabama,

like a giant cosmic shotgun blast hit our planet!

So there's hard work to be done.

We need more.

We need more data, more evidence.

We need to begin thinking science-fiction ideas,

and engineering them into science fact!

We need to see how we can do what we did with the airplane,

where we can now fly better than any bird,

or the submarine,

where we can swim better than any fish,

or now, rockets that can fly into space and come back and land on Earth,

and be reused -

unlike any animal ever!

Check out this map -

the light blue shows the continental shelf.

Most of that area was land 15,000 years ago.

What might be out there?

We need to make a bunch of cheap drones

with some kind of technology on board

that we can send swimming out under the oceans,

looking for ancient sites, roadways, seabed relics

that we've overlooked for thousands of years.

Or what about these big rocks

that have been sitting next to each other for an unknown amount of time?

Is there some technique we can develop

that will let us know how long they've been sitting there?

Have cosmic rays been zipping through them,

making little traces that we could read

and count up and tell us precisely how old they are?

Or what about surfaces?

We make a surface on a stone, What begins to change?

Does something in the atmosphere sink into the stone?

Does something in the stone come out over time

at a measured rate that we can also count up

and figure out a time on these amazing ancient artifacts?

Or there's this big pile of stones in Egypt.

A million stones piled up.

What are they doing to the ground underneath?

Have they been blocking it from something from the sun?

Can we compare what's underneath the pyramids to what's over here,

not covered up for that period of time?

Because the Egyptian records don't really tell us when the pyramids were built.

We're going to have to find that out!

Sometimes I feel like I'm still that four-year-old,

looking at the Earth,

trying to figure out how the pieces fit together.

One of my heroes, Carl Sagan,

reminds us that "Extraordinary claims require extraordinary evidence."

To that I would add

that extraordinary evidence deserves extraordinary investigation!

And I'm quite certain

that if we use our science and our human best thinking abilities,

and we do the hard work

and spend the money, find the answers,

we're gonna learn more about who we are,

where we came from,

and where we might be able to go.

And I think building the best possible future

is doable if we know what happened in our past.

So let's do it!

Thank you.

(Applause)