Articles About Eclipses (31)

Only a thin crescent of the Sun is visible against a dark sky during this partial solar eclipse Malaysia on 9 March 2016.

What Is a Solar Eclipse?

Solar eclipses happen when the Moon moves between Sun and Earth, blocking the Sun's rays and casting a shadow on Earth.

Black background with rays extending out from a circle and a bright light from the top of the circle.

How Often Do Solar Eclipses Happen?

There are between 2 and 5 solar eclipses every year, each one visible only in a limited area.

Zoomed in image of the Full Moon with its surface of craters and mountains.

Full Moon – the Moonlight Phase

The 3rd primary phase of the Moon, the Full Moon is the moment its disk is illuminated by the Sun's rays.

What's a Blood Moon?

A total lunar eclipse is often called a Blood Moon because of the red glow the eclipsed Moon gets. The term is also used for four total lunar eclipses that occur in a row.

2021 Cosmic Calendar

Celestial events and highlights of 2021 and 2022 including supermoons, solar and lunar eclipses, meteor showers, solstices, and equinoxes.

Illustration of the Moon's position in space in relation to Earth and the Sun at New Moon.

The New Moon

When is the next New Moon? New Moon is when the Sun and Moon are aligned, with the Sun and Earth on opposite sides of the Moon.

Solar and Lunar Eclipses

Solar and lunar eclipses, why they occur, when the next eclipse is, and from where you can see them.

Total Solar Eclipse

Total solar eclipses occur when the New Moon comes between the Sun and Earth and casts the darkest part of its shadow, the umbra, on Earth.

Total Lunar Eclipses

A total lunar eclipse happens when Earth's shadow blocks the direct light from the Sun reaching the Full Moon.

$Image of Full Moon red in color due to refraction with dark sky in the background.$

Lunar Eclipse: Red Moon

Find out why a totally eclipsed Moon turns a shade of red.

Astronomy Glossary - Terms & definitions

Astronomical Glossary - Terms & Definitions

What do astronomers really mean when they use those technical terms?

Solar Eclipse Myths

The solar eclipse has inspired many mythical stories and influenced human behavior. Even today, eclipses of the Sun are considered bad omens in many cultures.

Dark blue sky in the background with a glowing ring around the Sun. The center of the sun is dark.

Annular Solar Eclipse

An annular solar eclipse is when the Moon moves in front of the Sun but leaves the outer edge of the Sun visible as a ring of fire.

What Is the Umbra?

The umbra is the dark center portion of a shadow. The Moon's umbra causes total solar eclipses, and the Earth's umbra is involved in total and partial lunar eclipses.

Image of a faint eclipsed Moon behind a brightly it castle.

Watching Lunar Eclipses

A lunar eclipse can be seen with the naked eye, unlike solar eclipses, which have special safety requirements.

Picture with fields in the foreground and a crescent shaped Sun with Moon in front of it. Cloudy skies in the background.

Partial Solar Eclipse

A partial solar eclipse happens when the Moon only partially covers the Sun.

Why 3 Shadows?

The Earth and the Moon cast 3 different shadows: umbra, penumbra, and antumbra. Why are there 3 types of shadows and how are they defined?

Solar Eclipses in History

Solar eclipses were historically seen as omens that bring about death and destruction. People in many ancient civilizations tried their best to understand them.

A partially eclipsed Moon in the night sky. A little over half of the Moon is covered by a reddish shade.

What Is a Partial Lunar Eclipse?

A partial lunar eclipse happens when the Earth moves between the Sun and the Moon, but they are not precisely aligned.

Penumbral lunar eclipse illustration with positions of Sun, Earth, and Moon in space

What Is the Penumbra?

The penumbra is the lighter outer part of a shadow. The Moon's penumbra causes partial solar eclipses, and the Earth's penumbra is involved in penumbral lunar eclipses.

Mercury Transit

When Mercury transits the Sun, you can see it as a tiny black dot silhouetted against the Sun's disk. The last Mercury transit was on November 11, 2019.

Make a Pinhole Projector

Make a simple pinhole projector using 2 pieces of card or paper to safely watch a projection of a solar eclipse.

Annular solar eclipse illustration with positions of Earth, Moon, and Sun in space

What Is the Antumbra?

The antumbra is the lighter part of a shadow that forms at a certain distance from the object casting the shadow. It is involved in annular solar eclipses and planet transits.

Penumbral Lunar Eclipse

A penumbral lunar eclipse occurs when the outer shadow of Earth falls on the Moon's face. It is easy to miss this type of lunar eclipse.

Hybrid Solar Eclipse

A hybrid eclipse or annular/total eclipse starts as a total solar eclipse but changes into an annular solar eclipse. Why is that so? When is the next hybrid solar eclipse?

Eclipse Magnitude

Eclipse magnitude is a number that astronomers associate with solar or lunar eclipses. What does it mean?

Illustration of eclipse glasses, binoculars and telescope with eclipse safe lens with a green check mark next to them.

Safely See a Solar Eclipse

Protect your eyes during a solar eclipse. Sunglasses don't work.

Make a Box Pinhole Projector

Instructions on how to DIY a pinhole projector using a cardboard box and household items to safely see a solar eclipse.

Diagram of a DIY projector with binoculars.

Make a Solar Eclipse Projector

Make a Sun projector a pair of binoculars or a telescope to safely watch solar eclipses or a planet transit.

Transit of Venus: June 5-6, 2012

The 2012 Venus transit was the last chance to see this phenomenon for over 100 years. Mercury transits happen more often, the next one in 2032.

Solar Eclipses in 2017

Eclipses in 2017 are visible in Southern America and Africa, and Northern America.