There is a chance of observing a special astronomical event this weekend, as the night of May 15-16 will see a total lunar eclipse. It’s a great chance to stop and look up at the sky, and we’ve got info on how you can watch the event – whether you want to get out and see it yourself or stay warm inside and watch online.
What to expect from the Lunar Eclipse
An eclipse occurs when the moon is exactly opposite the Earth than the sun, so the Earth casts a shadow on the moon. It’s relatively common for there to be partial lunar eclipses, in which part of the moon is shadowed by Earth, but this weekend’s event is a rarer total lunar eclipse. This happens about once every one and a half years, when the moon is in full shadow.
As the Earth, Sun, and Moon move into place, you’ll see a shadow appear across the face of the Moon, moving over it until it completely blocks it. The shadow is called the umbra, and the point where it completely covers the moon is called the totality.
For a more in-depth explanation of how lunar eclipses happen and how they are different from solar eclipses or moon phases, NASA has a helpful video:
How to watch the lunar eclipse
The good thing about lunar eclipses is that, unlike solar eclipses, they are completely safe to watch and don’t require any special equipment. If you have binoculars or a telescope then this is a good excuse to get them out and observe the moon, but you can also see the eclipse with the naked eye – provided there are no clouds along the way, so cross your fingers for good weather.
It is also possible to view the eclipse from anywhere in the world where it is dark at the right times. In this case, that includes a full view of every stage of the eclipse from the eastern half of the United States and all of South America. Totality will also be visible from many other locations, including most of Africa and central Europe. Take a look at NASA’s interactive map to see when totality will occur where you are.
It should be easy to see the eclipse when it occurs. “Any half of the Earth in darkness during those hours will be able to see it,” NASA astronomer Alphonse Sterling said. “You don’t have to work too hard to find a good vantage point. Just get out!
The eclipse will also be an opportunity to see more stars, according to astronomer Mitzi Adams: “No moon means more stars visible,” Adams said. “During totality, if the sky is clear, we may even be able to see the Milky Way itself, appearing as a misty white river of stars stretching out in a curved arc.”
Watch the eclipse online
If you can’t go out, the weather is bad, or you’re somewhere that won’t be dark at the right time, you can watch the eclipse online. NASA has an eclipse feed with views from telescopes around the world, plus expert commentary. The stream begins at 11 p.m. ET (8 p.m. PT) on Sunday, May 15, and you can watch using the embedded video below: