See The Dawn Crescent Before Its African Eclipse

An annular solar eclipse happens across central Africa and Madagascar Thursday morning September 1 local time ( 4 a.m. CDT) when the sun will be below the horizon for observers in the Americas. Credit: Xavier Jubier
An annular solar eclipse takes place across central Africa and Madagascar Thursday morning September 1 local time ( 4 a.m. CDT) when the sun will be below the horizon for observers in the Americas. Credit: Xavier Jubier with additions by the author

Many of us are focused on next year’s total solar eclipse which will be widely visible across the U.S., but in truth, eclipses happen every year. Some are total, some are partial and some are annular. On Thursday, skywatchers across central Africa and Madagascar will witness the year’s second solar eclipse.

The first in March was total and cut a long but narrow lane across Indonesia and Indian Ocean. This one will be annular, meaning that the moon will be near the furthest point in its orbit and too small to completely cover the sun, leaving a ring of sunlight or ‘annulus’ at mid-eclipse. You’ll sometimes hear them referred to as ring eclipses.

This sequence taken during the May 20, 2012 annular eclipse from Red Bluff, Cal. shows the partial eclipse phases leading up to annularity, at right. Credit: Brocken Inaglory / CC BY-SA 3.0
This sequence taken during the May 20, 2012 annular eclipse from Red Bluff, Cal. shows the partial eclipse phases leading up to annularity, at right. Thursday’s African eclipse will follow a similar pattern. Credit: Brocken Inaglory / CC BY-SA 3.0

Observers in Europe, Africa and Asia will see the final eclipse of 2016 a little more than two weeks later on September 16, when the full moon dips into Earth’s outer shadow in penumbral eclipse. During maximum eclipse those paying attention will detect a grayish shading over the northern half of the moon.

This map shows the sky facing east-northeast about an hour before sunrise tomorrow morning (August 30), when the moon appears in the constellation Cancer low in the northeastern sky. Stellarium
This map shows the sky facing east-northeast about an hour before sunrise tomorrow morning (August 30), when the moon appears low in the northeastern sky in the constellation Cancer the crab. Use the opportunity to welcome back the constellation Orion and Sirius, the brightest star in the night sky. Orion will be well-place in the southeast at dawn. Stellarium

So how about something just about anyone can see? Well, we have that, too. Tomorrow morning (Tues. Aug. 30) you can catch a thin crescent moon at dawn low in the east-northeast sky starting an hour or so before sunrise. It will be tipped up on its side in a thin smile. With the sun rising later now, around 6:30 a.m., it doesn’t take quite as much effort to make a point of looking east if you’re up getting ready for school or work as it did in early summer. In June, twilight got underway at 4!

Like a sunrise or sunset, seeing a crescent moon at dawn or dusk gifts us with a sense of renewal. Two mornings later, the same moon will be new and busy covering the sun for a few hours before it returns to the evening sky this weekend.

Special note: Before you plan you a.m. viewing session, keep an eye out for aurora tonight. A minor storm is predicted to begin this afternoon and continue through 10 p.m. Central time tonight.