Election Day Eclipse

The second of two total lunar eclipses this year visible from Tucson will occur early next Tuesday morning, November 8. Yes, this is Election Day in the U.S. Having a total lunar eclipse on Election Day is so rare that it has never happened before since the United States was founded in 1776. Whether or not our nation survives its current paroxysms, we can rest assured that lunar eclipses will continue to occur as they have for billions of years.

Here are the local circumstances for Tucson, Arizona.

Time (MST)EventAltitude
1:02 a.m.Penumbral Eclipse Begins69˚
~1:45 a.m.Penumbra First Visible?62˚
2:09 a.m.Partial Eclipse Begins57°
3:16 a.m.Total Eclipse Begins44°
3:59 a.m.Greatest Eclipse35°
4:42 a.m.Total Eclipse Ends26°
5:23 a.m.Astronomical Twilight Begins18°
5:49 a.m.Partial Eclipse Ends13°
5:52 a.m.Nautical Twilight Begins12°

There are few astronomical events as impressive as a total lunar eclipse, and we’ll have a front-row seat Election Day morning.

Every month, the full moon passes close to the Earth’s shadow, but because of the Moon’s tilted orbit it usually passes above or below the shadow cone of the Earth. This month is different!

Tuesday morning, the Moon orbits right through the Earth’s shadow. At 1:02 a.m., the Moon dips his proverbial toe into the Earth’s shadow, when the Moon is 69˚ above Tucson’s SW horizon. This is the undetectable beginning of the eclipse, when the leading edge of the eastward orbiting-Moon “sees” a partial solar eclipse. When no part of the Moon sees anything more than the Earth blocking some but not all of the Sun, we call that a penumbral eclipse. The very subtle penumbral shading may just begin to be detectable around 1:45 a.m.

When the partial eclipse begins at 2:09 a.m., the upper left edge becomes the first part of the Moon to “see” a total solar eclipse. In other words, from part of the Moon now, the Earth totally eclipses the Sun.

Totality begins at 3:16 a.m. when all of the Moon sees the Earth completely blocking the Sun. Mid-totality occurs at 3:59 a.m., when the center of the Moon is closest to the center of the Earth’s shadow. At that moment, the Moon’s coppery color should be darkest.

That color is caused by sunlight refracting (bending) through the Earth’s atmosphere and shining on the Moon even though from the Moon the Earth is completely blocking the disk of the Sun. The reddish or orangish color imparted to the Moon during totality is the combined light of all the world’s sunrises and sunsets. What a beautiful thought! Had the Earth no atmosphere, the Moon would utterly disappear from view during totality—the time it is completely within the Earth’s umbral shadow.

Totality ends at 4:42 a.m., and the partial eclipse ends at 5:49 a.m. during morning twilight. When the last vestiges of partial solar eclipse leave the Moon at 6:56 a.m., the (penumbral) eclipse ends at moonset as the Sun is rising in the ESE.

This leisurely event can be enjoyed with the unaided eye, binoculars, a telescope, or all three. Don’t let anyone in the family miss seeing it!

The next total eclipse will not grace our skies until March 13, 2025.

If you haven’t already done so, please be sure to vote! It is your responsibility that comes with the privileges of your living in these United States. And voting should only be the beginning of your civic involvement. The quality of our government and elected representatives is directly proportional to the sum total of our collective civic involvement. And that has been pretty poor in recent years. Unlike an eclipse, democracy is not a spectator sport!

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