On April 8, a total solar eclipse will cross North America, passing over Mexico, the United States and Canada. A total solar eclipse happens when the Moon passes between the sun and the Earth, completely blocking the face of the sun and darkening the sky as if it were dawn or dusk in the middle of the day. But you’ll only get the full effect if you’re in what’s called the path of totality.
The upcoming eclipse will also be the last total solar eclipse visible from the contiguous United States until 2044. So if you want to see it there is a lot to know about safety and where to go to get the best experience.
NASA astrophysicist and Wisconsin Native, Michelle Thaller offers some suggestions and helpful tips to get the most out of this extraordinary event.
She begins by explaining the science behind a solar eclipse. "So basically, every month, we have a new moon and that means that the bright side of the moon is the one facing the sun. Next month, everything [will be] lined up so perfectly that when we have a new moon, we're actually going to pass through the shadow of the moon," Thaller explains. "The moon is going to cast a shadow on Earth and what that means is, if you happen to be lucky enough to be in the shadow, the sun will be covered up by the moon, and so the sky will go dark."
The outer atmosphere of the sun called the corona will be visible as well as stars and multiple planets. While the period of darkness varies depending on where you are, Thaller notes, "The longest possible is about four and a half minutes of darkness — of totality. The actual whole process of the moon beginning to pass over the sun, and what we call the partial eclipse, that can take up to 90 minutes or so — more than an hour."
Milwaukee isn't in the full shadow, but we will see 90% coverage. So, although the area will not be completely dark, it will still be an abnormal experience. Thaller says, "The sun will look almost like a crescent moon. The moon will almost cover it up, but there'll be a little sliver, and so all of those dappled shadows will look like crescents. And it's bizarre."
As Thaller explains, it's only safe to look directly at the sun during a total coverage eclipse. But there are tools and methods to safely view a partial eclipse, like using safety-rated eclipse glasses and certain types of welding goggles.
Even if you don't have any tools to look at the eclipse, if you walk outside during the eclipse where you can see how the shadows change to crescents. "If you can find anything with a little hole in it ... or if you take your hands and you make ... a peace sign with both of your hands, put your fingers close together and cross that and that will make a hole small enough to focus the sun [into the crescent shape]," Thaller explains.
The total eclipse shadow will travel over numerous cities, including Carbondale, IL, Indianapolis, Cleveland, San Antonio, Texas, and Dallas, Texas. Thaller recommends seeking out an opportunity to experience a total eclipse at some point. "I really encourage you sometime in your life to get into the absolute total shadow path because there's nothing like it. The sun can be 99% covered with just a tiny little bit of the sun's surface showing, and that's still bright enough to hurt your eyes to make the sky look bright. It really is kind of a yes or no. You're either in the shadow or not."
But if you're traveling to experience an eclipse, be sure to factor in plenty of time to account for traffic, which can be "horrendous," as Thaller suggests.
Here in Milwaukee the eclipse will peak around 1 o'clock in the afternoon. To help prepare everyone interested for the event, UW-Milwaukee's Manfred Olson Planetarium will be hosting informational sessions that include a free pair of eclipse safety glasses. Its director and Lake Effect contributor Jean Creighton will also share the profound impact the study of solar eclipses has had on scientific discoveries and our understanding of the universe.
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