Map Reveals How to See 2017's Incredible Total Solar Eclipse

Wherever you are in the U.S., here’s your best shot at viewing the solar eclipse on August 21.

This story appears in the August 2017 issue of National Geographic magazine.

On August 21, 2017, the moon will cast a shadow that will take a little over an hour and a half to traverse North America, plunging some areas into darkness for as much as two minutes, 41 seconds.

Total solar eclipses occur only when the moon is directly between the Earth and the sun—a rare occasion given the moon’s slightly tilted orbit. This summer’s eclipse—stretching from Salem, Oregon, to Charleston, South Carolina—will be the first total solar eclipse visible in the continental U.S. in 38 years.

But be advised: Never look directly at the sun except during totality, in the umbra, without proper eye protection.

THE DARKEST ARC

The sun will be totally obscured

by the moon in the approximately

70-mile-wide shadow called the

umbra. Outside this track, in the

penumbra, viewers should see a

partial eclipse.

UMBRA

Sun coverage

Portion of sun

covered by moon

Coronal streamer

Ionized gases stream outward

along magnetic lines of force in

dramatic displays that change

shape as the corona does.

Umbra

The shadow cast when the sun

is entirely blocked by the moon

what you

might see

EARTH

Penumbra

When the sun is partially

blocked by the moon

The sun’s corona—the

dramatic, outermost

atmosphere made of plasma

and superheated to an

unknown temperature—is

believed to be several million

degrees Fahrenheit. It’s visible

to the naked eye only during a

total solar eclipse, inside the

umbral shadow.

Coronal loop

On especially active areas of the

sun, plasma forms glowing arcs that

follow looping magnetic field lines.

MOON

PROMINENCE

Pinkish red arcs of plasma at the

edge of the solar disk may look

small, but they can be dozens of

times larger than the Earth.

what you might see

The sun’s corona—the dramatic, outermost atmosphere made of plasma and superheated to an unknown temperature—is believed to be several million degrees Fahrenheit. It’s visible to the naked eye only during a total solar eclipse, inside the umbral shadow.

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Coronal streamer

Ionized gases stream outward along magnetic lines of force in dramatic displays that change shape as the corona does.

Umbra

The shadow cast when the sun is entirely blocked by the moon

EARTH

Penumbra

When the sun is partially blocked by the moon

Coronal loop

On especially active areas of the sun, plasma forms glowing arcs that follow looping magnetic field lines.

MOON

PROMINENCE

Pinkish red arcs of plasma at the edge of the solar disk may look small, but they can be dozens of times larger than the Earth.

Sun Illustration is not to scale. THE SUN IS 400 TIMES as large as THE MOON AND 400 TIMES FARTHER FROM Earth than shown.

THE DARKEST ARC

The sun will be totally obscured by the moon in the approximately 70-mile-wide shadow called the umbra. Outside this track, in the penumbra, viewers should see a partial eclipse.

← Drag to explore →

Sun coverage

Portion of sun covered by moon

ON MAP, LOCAL DAYLIGHT SAVING TIME GIVEN.

Solar Eclipse 101 A total solar eclipse happens somewhere on Earth once every year or two. What is an eclipse? Learn more about how solar eclipses happen, the four types of eclipses, and how to view the sun safely if you're within the path of totality.

Eclipse map adapted with permission: https://www.exploratorium.edu/eclipse