Two weeks after May's lunar eclipse, the moon circles back for an encore and eclipses the sun. Just as lunar eclipses only occur at full moon, solar eclipses only happen at new moon, when the moon passes directly between the Earth and the sun. That will happen Thursday morning, June 10 . . . with a twist. Instead of total, this eclipse will be an annular.
The moon's apparent size varies along its elliptical orbit, appearing largest at perigee — when it's closest to the Earth, and smallest at apogee — its most distant point. This month, apogee occurs June 8, just two days before new moon. Even though it will pass directly in front of the sun, the moon won't completely cover it. We'll see the edges of the sun shining around the moon, creating a "ring of fire."
The annular eclipse path extends from the northern fringe of Lake Superior up to Hudson Bay, then arcs northwest over Greenland and the North Pole, where lucky polar bears and seals will experience 2 minutes, 36 seconds of annularity. From there the path swings southwest into Russia, with the eclipse ending at sunset in Siberia.
Some U.S. observers had planned to drive north into Canada to see annularity, but COVID-19 dashed those hopes. Canada's borders are still closed and won't reopen until sometime after June 21. But you needn't hang your head. Millions of Americans and Canadians will see something equally amazing: the sun rising in partial eclipse.
Depending on how much of the sun is covered for your location, you'll also experience falling temperatures, unusual lighting effects, a squished sun at the horizon and more. But it won't get nearly as dark as it does during a total eclipse, nor will the sun's outer atmosphere, called the corona, be visible.
From most of the U.S., greatest eclipse — when the maximum amount of sun is covered by the moon — happens around sunrise. That's why it's important to find a place with an unobstructed view to the northeast. If you can see it over a lake, all the better. Paired with its reflection, the obstructed sun will be that much more stunning.
The closer you live to the path of annularity the greater the eclipse. In Duluth, Minnesota, for instance, 47.8% of the sun will be covered at sunrise, though that drops to 40.7% by the time the sun climbs high enough to completely clear the horizon. Were I to drive north along the shore of Lake Superior to Grand Marais, that percentage would rise to 70.7% at sunrise. If instead I found myself in Minneapolis, 150 miles south of Duluth, the moon would cover just 23.0% of the sun.
Farther east in Europe and Asia, skywatchers will see a late-morning or afternoon partial solar eclipse. When you're out there watching, know that the moon will take a bite from the sun over the heads of billions of your fellow humans.
You can find out everything you need to know for your location by using the Interactive Solar Eclipse Map. Just type your location into the search box or zoom in by scrolling with your mouse. Clicking any location will pop up a box with all the pertinent details. Keep in mind that all times shown are Universal Time (UT). You can either convert those to local time as I described earlier or use this handy UT Converter. For a full explanation of each line in the pop-up box, click the blue "Help" link.
Because at least part of the sun will be visible throughout this eclipse you'll need eye protection. Never look directly at the sun for even a second. Solar infrared and ultraviolet (UV) light can damage your tender retinas before you know it.
|Winnipeg, MB||-----||5:21 a.m.||50.5%||Sunrise||5:56 a.m.|
|Fargo, ND||-----||5:33 a.m.||20.3%||Sunrise||5:52 a.m.|
|Armstrong, ON||-----||5:55 a.m.||97.2% (annular)||0.8°||6:53 a.m.|
|Duluth, MN||-----||5:15 a.m.||47.8%||Sunrise||5:49 a.m.|
|Minneapolis, MN||-----||5:27 a.m.||23.0°||Sunrise||5:47 a.m.|
|Chicago, IL||-----||5:16 a.m.||28.8%||Sunrise||5:39 a.m.|
|Philadelphia, PA||-----||5:33 a.m.||72.1%||Sunrise||6:30 a.m.|
|Charlotte, NC||-----||6:09 a.m.||16.8%||Sunrise||6:26 a.m.|
|New York, NY||-----||5:33 a.m.||72.5%||1°||6:31 a.m.|
|London, UK||10:09 a.m.||11:13 a.m.||20.0%||55°||12:23 p.m.|
|Munich, DE||11:37 a.m.||12:29 p.m.||6.3%||63°||1:22 p.m.|
|Warsaw, PL||11:55 a.m.||12:54 p.m.||10.0%||61°||1:54 p.m.|
|Espoo, FI||12:52 p.m.||2:04 p.m.||26.9%||52°||3:15 p.m.|
|Moscow, RU||1:22 p.m.||2:26 p.m.||15.7%||51°||3:28 p.m.|
|Beijing, CN||7:30 p.m.||-----||7.6%||Sunset||7:43 p.m.|
If you still have a pair of eclipse glasses from the August 2017 eclipse, inspect them for damage. As long as they're not scratched or full of pinholes they'll work for this eclipse, too. If you need a fresh pair, you can order one of these. Another good option is an inexpensive #14 welder's glass (not #13 or #12) from a welding supplier in your city or region.
You can also safely observe the eclipse indirectly in several ways:
1. Make a box pinhole projector. I saw my first solar eclipse as a kid with one of these. You'll find instructions here.
2. Take a thick pin and carefully make holes in a paper plate. Each hole will act as a "lens" and cast a small image of the eclipsed sun on the ground, a wall or a hand-held sheet of paper. You can also use a kitchen colander, which will project hundreds of tiny suns.
3. Lay one hand atop the other at a right angle to create small openings between your fingers that will project images of the sun on the ground or sidewalk.
4. Mount binoculars on a tripod and cover one lens, then use the other to project the sun's image onto a sheet of white cardboard or a wall.
In addition to changes in temperature and the quality of daylight around the time of maximum eclipse, keep your eyes and ears open for changes in animal or insect behavior especially if more than half the sun is covered from your city. A number of places, including my city of Duluth, lie within the negative zone of annularity, where the annular eclipse occurs shortly before sunrise.
From this zone, if you're up early at dawn, the sky would gradually brighten as usual, then pause (or even get darker?) as the sun goes into annular eclipse before re-brightening again at sunrise. Weird, eh?
There's even a small possibility that the ring of sunlight, while still below the horizon, could illuminate any clouds near the eastern sky in odd ways. Be sure to watch for these effects, and bring your camera!
Otherwise this eclipse will give us all a chance to participate in a four-body alignment — sun, moon, Earth and you, of course! Remember that's it's all happening in three dimensions, with the moon just 251,000 miles (404,000 km) away and the sun 370 times farther. All three large bodies will be in motion, with the moon traveling at 2,280 mph (3,660 km/hour), the Earth at 65,600 mph (29.3 km/sec) and the sun dragging the lot of us around the galactic center at more than 500,000 miles an hour (800,000 km/hour).
Is there ever such a thing as a dull day?
"Astro" Bob King is a freelance writer for the Duluth News Tribune. Read more of his work at duluthnewstribune.com/astrobob.