A penumbral lunar eclipse will occur Sunday night — assuming the sky is clear — and could be of some interest to Colorado skygazers.

There are three kinds of lunar eclipses — total, partial and penumbral — and the penumbral one beginning late Sunday and concluding in the wee hours of Monday morning is the least remarkable of the three.

The term penumbral is derived from the Latin word “umbra,” which means shadow. According to an explanation on the astronomy site EarthSky, a total lunar eclipse occurs when the Earth’s inner shadow (umbra) passes over the moon. In a partial lunar eclipse, the umbra covers only a portion of the moon.

“Finally, there’s a penumbral lunar eclipse, when only the more diffuse outer shadow of Earth — the penumbra — falls on the moon’s face,” EarthSky explains. “In fact, this third kind of lunar eclipse is much more subtle, and much more difficult to observe, than either a total or partial eclipse of the moon. That’s because there is never a dark bite taken out of the moon, as in a partial eclipse. So the eclipse never progresses to reach the dramatic minutes of totality. And at best, at mid-eclipse, very observant people will notice a dark shading on the moon’s face. Others will look and notice nothing at all.”

In other words, the full moon will grow dimmer but won’t disappear. Still, it may be worth a look if you’re not asleep. The eclipse will start at 10:53 p.m. Sunday, reaching maximum at 1:12 a.m. on Monday, and will end at 3:32 a.m.

A total solar eclipse is coming April 8 to parts of the U.S on a line from south Texas to Maine. Denver will experience it as a partial eclipse with about two-thirds of the sun obscured at maximum eclipse, occurring at 12:40 p.m., according to the time and astronomy website Time and Date. The eclipse will begin in Denver at 11:28 a.m. and conclude at 1:54 p.m.

The next total lunar eclipse in Denver will occur next March. The next total solar eclipse in Denver won’t occur until August of 2045.

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