An annular solar eclipse happens when the Moon covers the Sun’s center, leaving the Sun’s visible outer edges to form a “ring of fire” or annulus around the Moon.

Solar eclipses happen when the New Moon casts a shadow on Earth. The Moon’s shadow is not big enough to engulf the entire planet, so the shadow is always limited to a certain area. This area changes during the eclipse because the Moon and Earth are in constant motion: Earth continuously rotates around its axis while it orbits the Sun, and the Moon orbits Earth.

Solar eclipses are only visible from within the area where the shadow falls, and the closer you are to the center of the shadow’s path, the bigger the eclipse looks.

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.