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How many eclipses in 1 calendar year?

Every calendar year has at least 4, but 5, 6 or even 7 eclipses are also possible. Why don’t we see them all?

Possible to have 3 eclipses in 1 month?

In 1 calendar month, 3 eclipses are rare. But in 1 lunar month, 3 eclipses are are more common. From 2000-2050, it happens 14 times.

What’s a Blood Moon?

Nowadays, 4 totally eclipsed moons in a row are called Blood Moons. Why? We don’t know for sure, but the answer may lie in a 2013 book by 2 Christian pastors.

What is retrograde motion?

Retrograde motion of Jupiter or Mars or Saturn in our sky is an illusion, caused by Earth’s passing these slower-moving outer worlds. But there’s a real retrograde motion, too.

Circumpolar stars never rise or set

From Earth’s North and South Poles, all the stars appear as circumpolar. Meanwhile, at the equator, no star is circumpolar. And what about in between?

Two stars in Scorpius are harbingers of spring

Go ahead. Treat yourself to something beautiful, and hopeful: a glimpse of two stars that represented a Pawnee version of Groundhog Day.

Groundhog Day has roots in astronomy

Groundhog Day is tied to the movement of Earth around the sun. It’s the year’s first “cross-quarter” day.

When is the next Blue Moon?

Blue-colored moons are rare. But folklore has defined 2 other Blue Moons, too, which are more commonly seen. The next one will be 1 year from today.

Lengths of lunar months in 2017

Lunar months vary in part because the moon’s orbit around Earth isn’t a perfect circle. Longest (and shortest) lunar months in 2017, here.

Sun's path through the zodiac.

Ecliptic traces the sun’s path

The ecliptic is an imaginary line that marks the path of the sun. The signs of the Zodiac come from the constellations that lie along this line.