Differences in types of solar and lunar eclipses explained
A total solar eclipse will cut across Texas on April 8.
Cities that aren’t in the path of totality, including Houston, will see a partial solar eclipse.
And both of those experiences will be different from the annular solar eclipse that crossed the state last year.
Eclipse terminology can get confusing. Here’s more about the different types of eclipses and what viewers can expect to see:
Total solar eclipse
A total solar eclipse occurs when the moon passes between the sun and Earth. For those in the path of totality, the moon will completely block the face of the sun — darkening the sky as if it were dawn or dusk, according to NASA.
This is the only time it’s safe to look directly at the sun without special eclipse glasses.
Observers will see the sun’s outermost atmosphere (called the corona) that is usually hidden by the bright light of the sun’s surface. The viewing experience, however, is dependent on clear skies.
Total solar eclipses provide an opportunity for scientists to study the sun’s corona, and some researchers will chase the eclipse in NASA WB-57 planes.
Partial solar eclipse
A partial eclipse occurs when the moon passes between the sun and Earth, but the moon blocks only a portion of the sun because the alignment isn’t perfect.
It will look as if a bite has been taken out of the sun. It’s important to wear eclipse glasses when viewing a partial eclipse. Staring directly at the sun can cause eye injury.
Viewers in the April 8 path of totality will see a partial eclipse before and after the moon completely blocks the sun.
Texans who are not in the path of totality will only see a partial eclipse.
In Houston, the moon will block 94% of the sun at 1:40 p.m., according to Michael Zeiler with Greatamericaneclipse.com.
He said the sunlight will be dimmer — though not as dark as dawn or dusk — and shadows will be crisper.
The air temperature could drop by 10 to 15 degrees Fahrenheit.
Annular solar eclipse
An annular eclipse — also known as a “ring of fire” eclipse — occurs when the moon is farther away from Earth as it passes between the sun and the planet. It is too small to block the entire sun, so a “ring of fire” can be seen around the sun’s perimeter.
An annular eclipse crossed much of Texas last year.
The continental U.S. won’t see another annular solar eclipse until 2046, Rice University astronomer Pat Hartigan previously told the Chronicle.
Lunar eclipse
During a lunar eclipse, the Earth’s shadow is cast on the moon. A total lunar eclipse, often called a blood moon, turns the moon a reddish hue as sunsets from around the world are cast onto the lunar surface.
Solar eclipses are always accompanied by a lunar eclipse.
The lunar eclipse occurs during a full moon, and the solar eclipse occurs during a new moon, said Alex Young, NASA’S associate director of Heliophysics (the study of the sun and how it influences space).
The April 8 solar eclipse will be preceded by a lunar eclipse late Sunday and early Monday, but it won’t be a total lunar eclipse. Only part of the Earth’s shadow will cross the moon.
“It’ll be very faint,” Young said. “If you’re around a lot of city lights, you may not notice it. You probably have to be out in the countryside to notice the more subtle change.”