Lunar Eclipse, September 27, 2015

(NASA Photo)

On the night of September 27, the moon moves into the Earth’s shadow. Observers across the western hemisphere see a total lunar eclipse with the best part occurring from 9:11 p.m. through 10:23 p.m. No special equipment is necessary the eclipse.


The October 8, 2014 Total Lunar Eclipse.  The third eclipse in the current tetrad of total lunar eclipses.  See the text below.

Every planet and moon casts a two-leveled, round shadow into space. From the darker center of the shadow (umbra), the sun is completely blocked. From the outer shadow (penumbra), the sun is partly blocked. Because the moon shines from reflected sunlight, the moon loses its brightness when in passes into the umbra. Sunlight from the earth’s atmosphere gets bent into the shadow causing the moon to gently glow in a coppery color as in the image at the top of this posting.

Here are the events of the evening  (Times are for the Central Time zone, add or subtract time depending on your location)

Moon rise (Chicago): 6:34 p.m. (CDT) — The moon rises in the eastern sky.
Penumbral Eclipse:  7:11 p.m. (P1) — The moon begins moving into the outer shadow of Earth.  Casual observing will see not much difference between a full moon and this phase of the eclipse.
Partial Eclipse: 8:07 p.m. (U1) — The moon is within the lighter penumbral shadow and begins to move into the darker umbra.
Total Eclipse Begins: 9:11 p.m. (U2) — The moon is within the earth’s shadow and for the next 72 minutes the total eclipse occurs
Mid-Eclipse: 9:47 p.m. (Greatest) — The moon is midway through the shadow and midway through the eclipse.  This could be when the moon is at its darkest.
Total Eclipse Ends: 10:23 p.m. (U3) — The moon begins moving from the dark umbra.
Penumbral Eclipse: 11:27 p.m. (U4) — The moon is back into the penumbral shadow.  As earlier in the evening, not much difference is visible between the full moon and this part of the eclipse.
Eclipse Ends:  12:22 a.m. (September 28)
Moon set (Chicago): 7:16 a.m.

The moon and Mars were near each other during the lunar eclipse on April 15, 2014. Click the image to see the eclipsed moon, Spica, and Mars.

The 2016 Observers Handbook reports that this eclipse is the fourth consecutive total lunar eclipse in a series known as a tetrad.  This series of eclipse is rare.  The last tetrad occurred in 2003-2004.  The next tetrad series of consecutive total lunar eclipses is in 2032-2033.  There will be lunar eclipses during the intervening time, even total eclipses.  The tetrad is a series of four total eclipses with no other type in between.  Eight tetrads occur during the 21st century, according to the article.  Two of the images shown above are from this lunar eclipse tetrad.



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