Here Are Observation Times For Stages Of The Super Blood Moon Tomorrow Night

Diagram showing the conditions for  super blood Moon' total lunar eclipse tomorrow night. (From WSJ, Jan. 18, p. A3)


The excitement is building and the whole  astronomical community is readying  itself for the only total lunar eclipse of the year tomorrow night. And it will also be a "Super Blood Wolf Moon".  Why these terms? A 'blood Moon'  because the lunar surface appears reddish or ocher on account of being seen through the Earth's atmosphere. Thus, we observe the Moon, say in partial eclipse phase, as seen in the photo below:

 It is "super" in the sense of appearing larger than usual because of being much closer to the Earth, i.e. at its perigee point in orbit.  This has the Moon at 223, 000 miles distant as opposed to 251,000 miles at it apogee or most distant point. The 'wolf Moon'  just refers to a full Moon in January.   Nevertheless, it appears some stuffed shirt astronomers are upset at the use of the phrase for this total lunar eclipse (WSJ, today,  p. A1)  But as Zoe Learner of Cornell aptly put it, she has no problem as long as there are no inaccuracies., to which I concur.

As readers will gather from this discussion, lunar eclipses - which are relatively common (70 or so a year)-   only occur at the full Moon phase. The more detailed sketch below also helps to understand the stages of such eclipses:

Note the alignment (top) fixes the Sun at one end and the Moon at the other with Earth in between. The light  from the Sun - on intersecting the Earth -  produces a smaller, darker umbra and a lighter outer shadow cone called the penumbra.  If the lunar transit is such that the Moon (as seen from Earth ) only passes through the penumbra, we have a partial lunar eclipse.

If, on the other hand, the Moon passes through the darker umbra, we have a total lunar eclipse and what is called a "blood Moon" because the lunar surface appears reddish or ocher on account of being seen through the Earth's atmosphere. Thus, we observe the Moon as seen in the photo.

Now here are the eclipse stage time, all in Eastern standard time, which should be converted to your local standard time:

9: 36 p.m. -  Eclipse begins as Moon moves into the outer part of Earth's shadow (penumbra). The Moon appears slightly dim for about the next 37 minutes.

10:33 p.m. -   Moon starts to pass into the inner, darker part of the Earth's shadow (the umbra).  Moon will be seen to take on a darker hue.

11:41 pm.:   Moon will be completely inside the Earth's central shadow, and take on the reddish hue seen in the photo. See also above diagram. This total phase will last until 12: 43 a.m. when the Moon retreats from the central shadow and its color gets progressively lighter.

We will be out observing with our small refracting telescope. The good thing about the timing here is the next day is a federal holiday, so the kids ought to he able to stay up to see this natural wonder.  Much preferable to staring at cell phones!

"Super Blood Moon" Provided A Fantastic Sight

The Super Blood Moon as it appeared to us Sunday night at roughly 8:35 p.m. local time.


It isn't very often that two separate astronomical events occur in conjunction as they did Sunday night. That is,  the coincidence of a maximal area Moon (30 % larger than normal) along with a total lunar eclipse. The maximal area Moon is also called a "super Moon" because of the enhanced diameter and occurs because the Moon is at the point of its orbit called perigee - or the closest point to Earth.


The total lunar eclipse, meanwhile, occurs when the Moon passes completely  through the Earth shadow when Sun, Earth and Moon are in alignment. as depicted below:


Note the alignment (top) fixes the Sun at one end (left) and the Moon at the other with Earth in between. The light  from the Sun - on intersecting the Earth -  produces a smaller, darker umbra and a lighter outer shadow cone called the penumbra.  If the lunar transit is such that the Moon (as seen from Earth ) only passes through the penumbra, we have a partial lunar eclipse.

If, on the other hand, the Moon passes through the darker umbra, we have a total lunar eclipse and what is called a "blood Moon" because the lunar surface appears reddish or ochre on account of being seen through the Earth's atmosphere. Thus, we observe the Moon as seen in the photo we took.


As may be inferred from the diagrams, on account of the Earth casting a much larger shadow than the Moon (say when there are solar eclipses) the duration of lunar eclipses is longer, including the total phase. An entire lunar eclipse can last for hours as opposed to minutes for the solar eclipse.


Janice and I were fortunate that the weather was terrific and the sky perfectly clear when we went out at about 8:05 p.m. I had my binoculars (7 x 35mm) and Janice used a digital camera mounted on a tripod to take the photo. We took a series of about 8 photos, and decided the one displayed here had the best resolution.


Of course, though the sight may have even inspired fear in some - there were no supernatural associations to be extrapolated. It was a purely natural event that occurs every 2-3 decades. In cade you missed this one, you won't see another until 2033.