This means during most new moons, the shadow misses the Earth.
But there are two points in the moon’s orbit where the shadow can fall on the Earth. These are called nodes.
For a total eclipse to occur, the moon needs to be at or very close to one of the nodes.
3) The moon’s distance to the Earth
You might remember this from middle school science: The moon’s orbit around the Earth is not a perfect circle. It’s an ellipse.
There’s a point in the orbit where the moon is farthest away from the sun and a point where it’s closest. For a total eclipse to occur, the moon needs to be near its closest approach to Earth.
If the eclipse occurs when the moon is close, it will totally block out the sun. If it’s farther away, we get a ring of fire.
If you’re going to observe the eclipse, be careful!
On a normal day, staring straight into the sun can harm your eyes. An eclipsed sun is no different.
NASA warns: “It is never safe to look directly at the sun’s rays.” The intense light from the sun can damage your retina and cause a “permanent scotoma or ‘blind spot’ in the central vision,” according to the Lancet.
The intensity of light radiating from a partial or annular eclipse can still cause retinal damage. “Even when 99 percent of the Sun’s surface (the photosphere) is obscured during the partial phases of a solar eclipse, the remaining crescent Sun is still intense enough to cause a retinal burn, even though illumination levels are comparable to twilight,” NASA explains.
The safest way to observe an eclipse is indirectly — either by projecting it onto a screen through a pinhole or by looking through a specially designed filter.
If you miss this eclipse, there’s another one coming in 2024
If the weather doesn’t cooperate tomorrow (you can’t see an eclipse through clouds) or if you can’t make it to the path of the shadow, you’re not entirely out of luck. There’s another eclipse coming to the US in 2024. And that one will be a total eclipse, where the moon blocks out the entirety of the sun, creating a truly awesome view. During total solar eclipses, you can see the sun’s ethereal corona — its atmosphere — with the naked eye.
It will occur on April 8, 2024, and pass over much of the Eastern United States. Mark your calendars.