Get ready sky sleuths for an amazing lunar spectacle! A total lunar eclipse is coming up (weather permitting) after dark on Sunday, September 27th when the moon will turn an awesome reddish-orange as it enters the Earth’s umbra. The eclipse will be visible from most of North and South America.
Total lunar eclipses always happen at full moon. This is when the Moon is opposite in the sky as the Sun or put another way when the Earth is between the Sun and Moon. This situation allows for the Earth’s shadow to consume the Moon, and we see an eclipse.
As it turns out just a few days before this total lunar eclipse early on September 23rd the autumnal equinox occurs. The September or Fall equinox occurs at 3:20 a.m. CDT. In the northern hemisphere, the fall equinox marks the first day of fall (autumn). The full moon closest to the autumnal equinox is also traditionally called the harvest moon.
But wait, there’s more! Not only is this total lunar eclipse happening on the harvest moon it also coincides with the moon being at perigee (closest approach to Earth) and as luck would have it this particular lunar perigee is the closest yearly approach to Earth! What that means is this lunar eclipse will be happening at the point when the Moon will appear a little bigger in the sky than normal. Please don’t take that and run with it like Paul Revere! Some folks like to refer to this as a “Supermoon.” I would prefer not to call it that as it’s misleading. A Supermoon by definition is a full Moon or a new Moon at its closest point to Earth; also called perigee. A Supermoon looks around 12 to 14% bigger than its counterpart, the Micromoon. Again, I don’t like the terms “supermoon” and “micromoon.”This is mainly due to the fact that the vast majority observers will not notice the difference in either super or micro moon in the slightest. But yes,this eclipse will be occurring during lunar perigee and the moon will be slightly larger in the sky.
And if that was not enough, this is the fourth total lunar eclipse in a row, the others occurring on April 15, 2014, October 8, 2014 and April 4, 2015. This fourth total lunar eclipse completes a lunar tetrad. Lunar eclipses are also sometimes referred to as “blood Moon.” This has nothing to do with werewolves or Dracula but rather the rich reddish color that the total eclipsed Moon reflects. This color comes from light being refracted through the Earth’s atmosphere. Think about the red hues you see in the sky at sunrise or sunset.
So when to watch and at what time? The entire eclipse will last over 5 hours on Sunday evening September 27th and the only thing you really need to enjoy it is your eyes! However, binoculars are always a good option if you don’t have a telescope handy. Here in the Dallas/Fort Worth area the eclipse will already have begun (only slightly) when the Moon rises in the east. A little less than an hour after Moon rise the partial phase will begin. This is when the Earth’s darker shadow, the umbra, begins to bite into the Moon. You will want to have a good view of the eastern horizon so that your view is not obscured by trees or buildings. The Moon will rise higher in the sky and totality will begin at 9:11 p.m. and will continue for an hour and 12 minutes. This is the point when the Moon is totally in the umbra. Be sure to watch for changes in color as totality progresses. Totality ends at 10:23 p.m. and then there is still another hour of partial eclipse to go as the Moon slowly begins to illuminate.
