When the sun goes dark 5 questions answered about the solar eclipse

When the Sun goes dark: 5 questions answered about the solar eclipse

When the Sun goes dark: 5 questions answered about the solar eclipse .

A total solar eclipse will be visible across the US on Monday, August 21

Latest News A total solar eclipse will be visible across the US on Monday, August 21. Shannon Schmoll, director of the Abrams Planetarium at Michigan State University, explains why and how it happens, and what we can learn from an eclipse.

How do we know when an eclipse is going to happen?

How do we know in advance where it will be visible?

Solar eclipses happen when our view of the sun is blocked by the moon. When the moon lines up between the sun and Earth, the moon will cast a shadow onto Earth. This is what we on the ground observe as a solar eclipse.

We know when they’ll happen because over centuries astronomers have measured very precisely the motions of the Earth, moon and sun, including their orbital shapes, how the orbits precess and other parameters.

With those data about the moon – and similar information about the Earth’s orbit around the sun – we can make mathematical models of their movements in relation to each other.

Using those equations, we can calculate tables of data that can predict what we will see on Earth, depending on location, during an eclipse as well as when they will happen and how long they last. (The next major solar eclipses over the U.S. will be in 2023 and 2024.)

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