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Solar Eclipses: About

Annular Eclipse Path, 2023

total eclipse is different than an annular eclipse.

A total eclipse blocks the entire sun because it is closer to the sun. An annular eclipse is slightly further away from Earth and does not completely cover the sun; there is a ring of light around the moon.

According to Nasa, the Earth experiences a solar eclipses "season" two times a year in which an eclipse will occur. The Moon doesn't orbit in the exact same plane as the Sun and Earth do, therefore the type of eclipse will vary.

Total Eclipse Path, 2017

total eclipse is different than an annular eclipse.

A total eclipse blocks the entire sun because it is closer to the sun. An annular eclipse is slightly further away from Earth and does not completely cover the sun; there is a slight ring of light around the moon.

More about the 2017 Total Eclipse that passed over Salem.

The following is a list of total solar and lunar eclipses that have been or will be visible in Oregon in the next decade. Note that most are lunar  (moon) eclipses rather than solar (sun); total solar eclipses rarely take place in Oregon.

For a list of all eclipses that will be visible in Oregon, visit:

Jun 8, 1918 Total Solar Eclipse
Feb 26, 1979 Total Solar Eclipse
Aug 21, 2017 Total Solar Eclipse
Oct 14, 2023 Annular Solar Eclipse
Mar 13–14, 2025 Total Lunar Eclipse
Mar 3, 2026 Total Lunar Eclipse
Jun 25, 2029 Total Lunar Eclipse
Oct 8, 2033 Total Lunar Eclipse


During a Total Eclipse

Temperature Drop

The drop in temperature is very noticeable during an eclipse, depending on your location, length of eclipse, and amount the Sun is covered. This graph shows a 16 degree drop at Antarctica over 90 minutes.



Phases of an Eclipse



Animal Behavior

Wild animals have been known to treat an eclipse like an abrupt night. Songbirds may retire to where they normally sleep, perform their typical dusk serenade and then quiet down. When the eclipse ends, they interpret it as morning and respond with a dawn chorus. The disruption is often brief and reportedly does not throw off the internal clocks of birds.

Pets and other non-wild animals often have relatively mild reactions to an eclipse. Dogs and cats may be confused by a sudden dimming of the light but are largely unaffected.


Solar Eclipse Diagram

The shadow, called the umbra, has a well defined diameter but the size varies a lot due to variation in the distance from the Moon to the Earth since it's orbit is not circular. Sometimes the Moon is so far away that it can't fill the Sun and there is no umbra at all, that's called an annular eclipse. The umbra spans roughly 60-100 miles (100-160kilometers) in area.


Shadow Size (Umbra)

It is hard to pin down the size of the penumbra (Moon's shadow) because it fades near the edges. According to Astronomy Stack Exchange, if you could see the very edges, then it would be twice the diameter of the moon or roughly 4,200 miles total (6,900 kilometers). It will also vary in size as the shadow travels across the surface of the Earth. Directly over the center of the Earth will cover a smaller area than where the shadow would land along the "edges" of the Earth's curved surface.


The Corona

The Sun’s corona is the outermost part of the Sun’s atmosphere.

The corona is usually hidden by the bright light of the Sun's surface which makes it difficult to see without using special instruments. However, the corona can be viewed during a total solar eclipse. Below is a stunning look at the Sun's corona during a total solar eclipse. The second image shows the Sun's surface and atmosphere. It was taken by NASA with special instruments and shows coronal streamers, loops, and plumes of charged particles. 

image of the sun's corona

Safely View a Solar Eclipse



Like a magnifying glass, an eye lens focuses the sun's light onto a small part at the back of your eyes. Your eye has no pain receptors, so you will not feel the damage occur.  The only safe time to look at the sun is when the moon completely blocks it. 

Quick and Easy Options

Hold up both hands with fingers overlapping at right angles. The holes between your fingers make pinholes. Look at shade trees where light break through the leaves to make pools of light. Most things with holes will work!





Use a mirror to reflect the sunlight into a wall
or shadowy area.


Eclipse Glasses

The easiest and one of the most safest ways to observe an eclipse and relatively cheap ($12 for pack of 5). Make sure that the glasses have "ISO 12312-2" printed on them and they would be made in 2015 or after.  Most welding goggles aren't heavy duty enough; they must be at shade 14 and higher to be dark enough to meet transmittance requirements ISO 12312-2. 



The simple method is to allow light to travel through a binocular and reflect onto the ground or piece of paper.


NEVER look at the sun through binoculars!


You can also mount binoculars onto a stand, cover the area around the eye pieces, and shine the light onto a piece of paper. Be careful about exposing the binoculars to too much light/heat; the plastic inside could melt.




Pinhole Projector

1. Use a long box or tape several boxes together--the longer the better.
    Alternatively, use a shoe box. The projection will be much smaller.
2. Cut a large hole in one end of the box
3. Then tape a piece of tin foil over the hole and poke a small hole in the foil with a pin.
4. At the end, cut a good-sized hole on the side of the box to view the projection.
5. Place white paper at the end of the box to make the eclipse more visible.
6. Aim the spot of light onto the white paper.  

Willamette University

Willamette University Libraries

Mark O. Hatfield Library
900 State Street.
Salem Oregon 97301
Pacific Northwest College of Art Library
511 NW Broadway.
Portland Oregon 97209