We've all heard about solar eclipses, right?

and you're probably aware that there's a huge one coming very soon

so, you think about how to prepare and you're thinking, maybe I gotta get some special goggles

so that when I'm looking up at the sky and I see the moon come across I don't hurt my eyes

so I can see totality by looking directly at the sun or something like that, right?

It's actually far more complicated and far more beautiful than that.

There are very specific moments that happen during a solar eclipse

That if you're prepared for 'em, down to the second, you can see really neat things that you didn't know about before.

So, today on Smarter Every Day, there's this hyper-meticulous guy in my hometown.

when I say meticulous, just look at what he does for a living

Anyway, this guy has chased eclipses all over the world--eclipsees, I don't know,

Anyway, this guy is like, having a meeting right now, with all his buddies

They're going to plan, down to the second, where they're going to be.

So they can see these individual events, not just totality, but there's other stuff that happens.

Anyway, let's go bust up in here

And let's figure how to scientifically watch

an eclipse. Let's go.

Can I bust up your meeting and ask you a question ?

Yes, sir. This is Dr.Gordon Tulipan.

He's a well-respected plastic surgeon by day

known for great attention to detail.

So why are you guys here listening to this guy?

*Laughter* 'Cause he's the man?

I'm here because he's known as

an eclipse fanatic.

He's travelled the world to film eclipses

And he's even been invited to give talks at NASA.

At the meeting, I told Dr. Tulipan

I wanted to go to my son's baseball game so

he agreed to meet with me the following day

in his conference room.

By the way, my oldest son found his baseball swing this year

and I love to watch him play.

I came back the next day for a one-on-one

eclipse study session with Dr.Tulipan.

I got a good show for you.

DESTIN>> So I guess your ultimate goal is to

prepare people for this eclipse

GORDON>> and to inspire them not to miss it.

This eclipse is

going to be a once in a lifetime thing for

a lot of people. People are not going to travel

all over the world to go to eclipses

like I do. It's a wonderful thing to have

an eclipse in your country

you can drive to, and when I show you

the world map of the eclipses that

are going to happen in the next twenty years,

you'll understand how difficult it is

to get to a total solar eclipse with you son.

He started with the basics. He first explained

how magical it is that our Moon and Sun

are almost exactly the same size

in the sky even though they're very

different celestial bodies. The Moon orbits

the Earth in an ellipse.

This means as it gets closer to us, it looks bigger

and as it gets further away from us, it looks smaller.

The really cool thing about this is that

at the smaller size, it doesn't quite cover the Sun.

But at the largest size, it does.

This means that there's two major types of

eclipses. An anular eclipse

occurs when the Moon doesn't totally block out

the Sun. It looks like

a bright glowing solar disk poking from behind

the Moon. When the Moon is larger,

it does block out the Sun.

This of course is a total eclipse.

Eclipses are few and far

between but only a few hitting each continent

over the course of several decades.

The red curves here show annular eclipses

where the Moon is smaller than the Sun.

So as you can imagine the

total eclipses which are shown here in blue

are extra special sweet.

If one of these is in the country where you live,

you really need to figure out how

to drive to it. These narrow bands where

the eclipse Moon shadow moves over the ground is called the totality plane.

You have to be within the band to see

a total eclipse, but it's not just ok to be within the band,

You goal should be to get to

the very centre of the band. At the edges,

the totality only lasts a few seconds.

But down in the centre, it can last for

several minutes. Gordon explained that the most

important thing about wherever you're watching the eclipse from

is called the contact times.

C1, or Contact Time 1,

is the exact instant

when the lunar disk touches the solar disk

in the sky. The Moon then continues

to move accros the Sun for quite some time.

This can usually take over an hour.

Then,

C2 happens. C2 is the exact

second when the lunar disk

covers the Sun.

C3 is the moment that the Sun pokes out from behind

the Moon again. It then traverses for

probably an hour or so and then C4

happens.

C4 is the exact moment that the Moon quits

covering the Sun at all.

GORDON>> What I'm telling people to do is

not to miss the partial phase phenomenon

which are the other things

that happen before totality.

You're surroundings change.

The temperature changes,

the lighting changes, the

animals get confused because they think

that nighttime is falling, and if

you're really lucky, you'll get to see

shadow bands, and shadow bands don't happen

at every eclipse and they don't

happen at every observing area.

DESTIN>> What are shadow bands ? GORDON>> It bends the

light and causes

motions of

serpentine shadows

accros the ground

that look like thousands of

snakes crawling

in unison... DESTIN>> Shut up !

GORDON>>... in parallel going away from you DESTIN>> This is bull.

GORDON>> and to the side. DESTIN>> There's no way that happens.

GORDON>> It's unbelievable. I saw them in 2002.

DESTIN>> No ! GORDON>> Absolutely.

DESTIN>> You're saying...

You're saying it's gonna... it might...

look like snakes

crawling on the ground ? GORDON>> Very thin

cause they're little ground shadows

and the way I perceive them

is, picture thousands of

parallel snakes, going like this

going away from you

and to one of the sides depending on...

DESTIN>> WHAT ??? Snakes ?

I thought an eclipse was like, you know,

I'm gonna look at the... NO !

It's about shadow bands for me now.

Here's the deal, in 1842, this guys

was like "it was so striking

that children were running around trying to

grab those things with their hands".

This is a real phenomenon.

I've looked it up, and scientists

do not know what causes it.

They have like

a ton of theories. They don't know. To me, it sounds like

an optical interference thing.

But they don't know. And not a good video on

the internet. There's some videos

but it such a low contrast event

that nobody has ever captured it really well.

So the obvious question,

for Mr Solar-Eclipse-Expert,

is how do we get a good

video of shadow bands ?

How do we capture it ? When does it happen ?

DESTIN>> Just before C2 ? GORDON>> Just before C2 and

just after C3 when

the Sun is a slit. It has

to be that final little narrow slit

otherwise it doesn't work.

DESTIN>> How long does it last?

GORDON>> For about 20 or 30 seconds.

You have to catch it. DESTIN>> So you have to know

it's about to happen. GORDON>> Exactly.

DESTIN>> I rarely ask people to do things,