- A total eclipse is one of the rarest and most spectacular events in nature.

For the first time since 1925, Western New York will experience a total solar eclipse, an amazing celestial event where the light of the Sun is completely blocked out by the Moon, and we are in the path of totality as a wise man once said, where would you rather be than right here, right now.

(audience applauding) In this episode of "Compact Science," we are going to explore the science of eclipses.

(upbeat music) Civilizations throughout history have paid special attention to eclipses.

The ancient Greeks believe that they were a sign that the gods were angry with humans and that the Sun would abandon the Earth.

The word eclipse actually comes from the Greek word meaning abandonment.

An eclipse played a role in the unification of the Haudenosaunee Confederacy and the development of the great law of peace.

For millennia those brief minutes have also brought moments of brilliant discovery, everything from learning about the laws of physics, the chemistry of the Sun, and the size, shape, and distance of celestial bodies.

To understand what an eclipse is, we have to look at our solar system.

At the center is our Sun.

Our Sun is a star just like the ones we see in the night sky.

There are planets circling a lot of those stars too, but that's an another story.

The Sun is the biggest, most massive object in our solar system.

It's a huge source of light and heat and has a strong gravitational pull.

This helps keep all of the planets in orbit.

An orbit is a curved path of a celestial object around another object.

So planets orbit the Sun, but there are other things that orbit the planets too.

These are called moons.

The Earth has one moon, but other planets have way more.

Jupiter, for example, has at least 95 moons.

We may not notice that we're constantly in motion, but we can tell by the way the Sun moves in the sky and how the environment changes around us over the course of a year.

Actually, we're on quite a ride.

The Earth orbits around the Sun at a speed of 67,100 miles per hour.

That's the equivalent of traveling from London to New York in about three minutes.

So planets orbit around suns and moons orbit around planets.

Sometimes these celestial bodies block out the Sun's light and cast shadows on one another.

This is an eclipse.

On Earth, we observe two main types of eclipses, lunar and solar.

In the case of a lunar eclipse, the light from the Sun, which usually bounces or reflects off the Moon, is blocked out by the Earth itself.

The Earth gets in between the Sun and the Moon.

Solar eclipses occur when the Moon blocks out the light from the Sun, so the Moon gets in between the Sun and the Earth.

Although the Moon is much smaller than the Sun, the Moon is also much closer.

The diameter of the Moon is roughly 400 times smaller than the Sun, but by amazing coincidence, it also happens to be about 400 times closer to the Earth.

So during a total solar eclipse, the two bodies are at just the right distances to make them appear to be the same size in our sky like a cosmic optical illusion.

(dramatic music) Not every solar eclipse is a total solar eclipse.

During a solar eclipse, the Moon passes between the Earth and the Sun and blocks all or part of the Sun.

The Moon's orbit around the Earth is not quite circular.

At times, it's closer to us than others.

As a result, the Moon's apparent size changes over time.

We call the Moon's closest point to Earth, perigee and its farthest point from Earth is apogee.

During a total solar eclipse, the Moon lines up perfectly fully blocking out the Sun while near perigee.

In a partial solar eclipse, the Moon only blocks out part of the Sun, and during an annular eclipse, the Moon is near apogee too far away from the Earth to completely block out the Sun.

But you still see a ring of light in the sky.

Two shadows are cast during an eclipse.

The first is called the umbra.

It's the dark center of the eclipse shadow.

It's the part of the shadow where all light is blocked.

The larger partial shadow is called the penumbra.

While the Earth rotates or spins on its axis, the Moon shadow travels along a path spanning hundreds of miles on the Earth's surface.

The path of the Moon shadow is called the path of totality.

During the eclipse, anyone within the path of totality will experience darkness for a few minutes while in the Moon's umbra shadow.

The closer you are to the center line of the umbra's path, the longer totality lasts.

Weather permitting people along the path of totality will see the Sun's corona or outer atmosphere, which is usually obscured by the bright face of the Sun.

Those outside the path of totality in the penumbral shadow of the Moon will experience a partial solar eclipse where only part of the Sun is blocked out.

The path of totality for the 2024 eclipse stretches across North America, from northern Mexico to northeast Canada.

Depending on where you are, you can view the eclipse beginning anywhere from around noon to 4:00 pm.

Here in Buffalo, the celestial show begins at about 2:04 pm and we will reach totality at 3:18 pm.

Just before totality, we may see a feature called, the diamond ring or Baily's Beads.

These are the last sharp points of sunlight, visible, shining through the valleys at the edge of the Moon.

If the skies are clear, Jupiter and Venus, the planets is closest to the eclipse Sun may be visible as well as the Sun swirling atmosphere.

But even if it's a cloudy day, this eclipse is still worth experiencing for three and a half minutes.

In the middle of the day, the sky will darken as if it were dawn or dusk.

The temperature will drop and you may even notice animals behaving differently.

An eclipse is something you won't want to miss, but you must observe them safely.

You never want to look directly at the Sun, especially not at a solar eclipse.

Protect your eyes at all times.

The only safe way to look directly at the Sun is through solar filters such as eclipse glasses, homemade filters, or ordinary sunglasses.

Even very dark ones are not safe for looking at the sun.

Proper eclipse glasses are thousands of times darker than sunglasses.

You can also look indirectly at the Sun by watching the shadows or making a quick and easy pinhole projector.

The only time it is safe to remove your eclipse glasses is during the few minutes of totality.

Ever wonder why solar eclipses don't happen more often?

Well, the Earth, Moon and Sun don't line up perfectly every month because the moon's orbit is tilted by about five degrees compared to the Earth's orbit around the Sun.

Most of the time, the Moon shadow misses our planet.

The true rarity of a total eclipse comes not from how often one takes place, but from the fact that each one is only visible from a tiny fraction of the Earth's surface, less than 1%.

The path of the 2024 total eclipse only covers one half of 1% of the Earth's surface.

Scientists estimate that a random point on Earth either sees a total or an annular eclipse on average of every 140 years.

This eclipse, like all eclipses, is a window into the workings of the universe.

Eclipses had and still have a lot to teach us.

(upbeat music) We learned about the cosmic confluences that occur when the Sun, Moon, and Earth align.

If you're interested in learning more, check out our Compact Science Viewer Challenge.

We have a fun eclipse experiment that you can try at home that's all about perspective.

Get all the instructions on our website and be sure to share back your results.

I'm Sarajane Gomlak-Green, and you have been watching "Compact Science."

Until next time, stay curious.

(upbeat music) - [Announcer] Compact Science is funded in part by the Joy Family Foundation and the New York State Department of Education.

- We're going to explore the science of eclipses.

♪ Eclipses, eclipses ♪ (soft upbeat music) All right, I'm so sorry, but how's everyone doing?

(soft upbeat music) Mi, mi, mi, mi mi - [Camera Crew] High energy.

(soft music) - Eclipses, okay.