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.

At new moon phase, the moon passes between the sun and the Earth. We don't experience eclipses every new moon because the moon's orbit is tilted with respect to Earth's orbit. Ordinarily, the moon passes a small distance above or below the sun at new moon. (Bob King)
At new moon phase, the moon passes between the sun and the Earth. We don't experience eclipses every new moon because the moon's orbit is tilted with respect to Earth's orbit. Ordinarily, the moon passes a small distance above or below the sun at new moon. (Bob King)

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."

In this global map, the path of annular eclipse is highlighted in orange, while timelines and the percentage of the sun covered during the eclipse are shown for many locations. Times are UT or Universal Time. To convert to Eastern Daylight Time (EDT), subtract 4 hours; 5 hours for CDT; 6 hours for MDT and 7 hours for PDT. (Michael Zeiler / www.GreatAmericanEclipse.com)
In this global map, the path of annular eclipse is highlighted in orange, while timelines and the percentage of the sun covered during the eclipse are shown for many locations. Times are UT or Universal Time. To convert to Eastern Daylight Time (EDT), subtract 4 hours; 5 hours for CDT; 6 hours for MDT and 7 hours for PDT. (Michael Zeiler / www.GreatAmericanEclipse.com)

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.

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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.

In an annular eclipse the Moon is at or near apogee, and the lunar disk appears too small to cover the Sun. Observers situated in the antumbra — where the eclipse is annular — see a ring of sunlight instead. In a total eclipse, the moon appears larger and its shadow (umbra) extends all the way to the Earth's surface.
(Eclipse Predictions by Fred Espenak, www.EclipseWise.com)
In an annular eclipse the Moon is at or near apogee, and the lunar disk appears too small to cover the Sun. Observers situated in the antumbra — where the eclipse is annular — see a ring of sunlight instead. In a total eclipse, the moon appears larger and its shadow (umbra) extends all the way to the Earth's surface. (Eclipse Predictions by Fred Espenak, www.EclipseWise.com)

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.

This map displays the appearance of the sun at maximum eclipse for locations across the U.S. and southern Canada. Those living closest to the eclipse-in-progress-at-sunrise line will see the most sun covered. (Michael Zeiler / www.GreatAmericanEclipse,com)
This map displays the appearance of the sun at maximum eclipse for locations across the U.S. and southern Canada. Those living closest to the eclipse-in-progress-at-sunrise line will see the most sun covered. (Michael Zeiler / www.GreatAmericanEclipse,com)

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.

This is an example from the Interactive Solar Eclipse map centered on Grand Marais, Minn. I've highlighted the sunrise time and the percentage of the sun blocked by the moon at sunrise. I also subtracted 5 hours from the time shown to convert UT to Central Daylight Time. The obscuration value (left box) will display "???" if the sun is below the horizon at maximum eclipse. For any location where the obscuration = ??? you'll see the most sun covered right at sunrise. (Xavier M. Jubier)
This is an example from the Interactive Solar Eclipse map centered on Grand Marais, Minn. I've highlighted the sunrise time and the percentage of the sun blocked by the moon at sunrise. I also subtracted 5 hours from the time shown to convert UT to Central Daylight Time. The obscuration value (left box) will display "???" if the sun is below the horizon at maximum eclipse. For any location where the obscuration = ??? you'll see the most sun covered right at sunrise. (Xavier M. Jubier)

This example highlights the eclipse circumstances at Boston, Mass. The sunrise time and percent obscuration at that moment are highlighted in black. Wherever maximum eclipse occurs AFTER sunrise, the obscuration value (left, in red) will give the percentage covered, in this case 72.847%. You'll find the time of maximum eclipse in the second to last line. (Xavier M. Jubier)
This example highlights the eclipse circumstances at Boston, Mass. The sunrise time and percent obscuration at that moment are highlighted in black. Wherever maximum eclipse occurs AFTER sunrise, the obscuration value (left, in red) will give the percentage covered, in this case 72.847%. You'll find the time of maximum eclipse in the second to last line. (Xavier M. Jubier)

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.

CityStartMax. Eclipse ObscurationAltitudeEnd
Winnipeg, MB-----5:21 a.m.50.5%Sunrise5:56 a.m.
Fargo, ND-----5:33 a.m.20.3%Sunrise5:52 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%Sunrise5:49 a.m.
Minneapolis, MN-----5:27 a.m.23.0°Sunrise5:47 a.m.
Chicago, IL-----5:16 a.m.28.8%Sunrise5:39 a.m.
Philadelphia, PA-----5:33 a.m.72.1%Sunrise6:30 a.m.
Charlotte, NC-----6:09 a.m.16.8%Sunrise6:26 a.m.
New York, NY-----5:33 a.m.72.5%6:31 a.m.
London, UK10:09 a.m.11:13 a.m.20.0%55°12:23 p.m.
Munich, DE11:37 a.m.12:29 p.m.6.3%63°1:22 p.m.
Warsaw, PL11:55 a.m.12:54 p.m.10.0%61°1:54 p.m.
Espoo, FI12:52 p.m.2:04 p.m.26.9%52°3:15 p.m.
Moscow, RU1:22 p.m.2:26 p.m.15.7%51°3:28 p.m.
Beijing, CN7:30 p.m.-----7.6%Sunset7:43 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:

Mylar eclipse glasses offer a safe, easy way to observe a solar eclipse. You can also use projection methods including binoculars (left) or your crossed hands to project tiny images of the eclipsed Sun on the ground below. The spaces between leaves on a tree will also cast images of the eclipsed sun.
Bob King (left, center) and Sealle / CC BY-SA 4.0 (right)
Mylar eclipse glasses offer a safe, easy way to observe a solar eclipse. You can also use projection methods including binoculars (left) or your crossed hands to project tiny images of the eclipsed Sun on the ground below. The spaces between leaves on a tree will also cast images of the eclipsed sun. Bob King (left, center) and Sealle / CC BY-SA 4.0 (right)

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.

Within the negative path of annularity maximum annular eclipse occurs shortly before sunrise. Observers in this zone should be alert for unusual twilight effects. (Gregg Dinderman / used with permission from Sky & Telescope (skyandtelescope.org)
Within the negative path of annularity maximum annular eclipse occurs shortly before sunrise. Observers in this zone should be alert for unusual twilight effects. (Gregg Dinderman / used with permission from Sky & Telescope (skyandtelescope.org)

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?

Duluth, Minnesota, lies in the negative annularity zone with the Sun in annular eclipse 3.8° below the horizon shortly before it rises. People living in that special zone should be alert for unusual twilight effects. (Stellarium)
Duluth, Minnesota, lies in the negative annularity zone with the Sun in annular eclipse 3.8° below the horizon shortly before it rises. People living in that special zone should be alert for unusual twilight effects. (Stellarium)

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.