Not-Quite-Total Lunar Eclipse

Dear Friends –

Tomorrow night, Thursday Aug. 27, 2026 (into Friday morning, Aug. 28): a not-quite-total lunar eclipse visible to almost everyone in the central/eastern Pacific, North and South America, Europe,  and Africa. The “not-quite-total” refers to the fact that rather than having Earth’s shadow completely cover the Moon (as in a total lunar eclipse), in this case Earth’s shadow  will cover about 96% of the Moon at maximum. This means we won’t get the full “blood moon” effect in which the eclipsed Moon turns red in color. However, we should still see some redness on the shadowed portion of the Moon, and we’ll also see my favorite part of lunar eclipses: watching Earth’s clearly curved shadow as it moves across the Moon, providing one of many forms of proof that Earth is round.

The timing is especially good for those of us in the US (including Hawaii) who’d like to watch it without having to stay up too late. Here’s a brief summary of the key times for the U.S. by time zone (see this Time and Date page for more details) for the start, maximum, and end of the partial eclipse (the time during which you’ll notice Earth’s shadow moving across the Moon):

• Hawaii time: Partial begins at 4:33pm, maximum at 6:13pm, partial   ends at 7:52pm.
• Alaska time: Partial begins at 6:33 pm, maximum at 8:13 pm, partial  ends at 9:52 pm.
• Pacific time: Partial begins at 7:33 pm, maximum at 9:13 pm, partial  ends at 10:52 pm.>
• Mountain time: Partial begins at 8:33 pm, maximum at 10:13 pm, partial  ends at 11:52 pm.
• Central time: Partial begins at 9:33 pm, maximum at 11:13 pm, partial  ends at 12:52 am.
• Eastern time: Partial begins at 10:33 pm, maximum at 12:13 am, partial  ends at 1:52 am.

Very brief Q&A:

• Q: Why is this lunar eclipse coming just 2 weeks after the total solar eclipse that occurred over Greenland, Iceland, and Spain?
  A: Solar and lunar eclipses always come in pairs 2 weeks apart, with the solar eclipse at new moon and the lunar eclipse at full moon. This is a result of the fact that the periods in which Sun, Earth, and Moon are aligned closely enough for eclipses to occur, called “eclipse seasons,” last close to 5 weeks, so that there is always enough time for at least one solar and one lunar eclipse in each eclipse season.
• Q: Why is the lunar eclipse visible to so many more people than the solar eclipse?
  A:  During a lunar eclipse, anyone who can see the full Moon — which means anyone on the night side of Earth — will be able to view the eclipse. In contrast, during a solar eclipse, the Moon’s  shadow touches only a relatively small region of Earth, limiting the number of people who can see it.
• Q: Why does the Moon turn reddish in color during totality or near-totality?
  A: When sunlight is blocked by Earth, the only light reaching the Moon comes from Earth itself — and in particular from the ring-shaped “edge” of  Earth’s atmosphere that can be seen from the Moon, which is where people on Earth are seeing the reddish color of either a sunset or sunrise.
• Q: You mention that lunar eclipses offer one of many forms of proof that Earth is round. What are some of the others?
  A: For much more extensive lists, see: (1)  Section 3.1.1 of my FREE online Earth and Space Science text, and in particular the group activity on “debunking flat Earthers”; (2)  Teacher Note 12 in my book The Scale of the Universe.
• Q: Where can I learn more about this and other eclipses?
  A: To learn more about how eclipses work in general, check out my two short videos about understanding eclipses posted here (and also accessible through the Learn screen of the FREE Totality app) or my Totality!  book.

Other reminders:
Totality in 2027 and 2028: There will be fantastic total solar eclipses in both 2027 and 2028  (maps below are screenshots from the Totality app). I highly encourage you to consider making a trip around one or both of these. Please note that I’ll be speaking on the following tours (click the links for details and pricing, and please tell them that I sent you):

• 2027: Doug Duncan’s eclipse trip in Gibraltar — sold out, but they are taking a wait list.
• 2028: the Astronomy Magazine Australia eclipse cruise.

The Scale of the Universe: If you are interested in hearing me speak about my new book, please check out the following:

• TV interview on Great Day Colorado, including brief tour of the CU Voyage Scale Model Solar System: https://youtu.be/nSNIzsbJ2OA?si=9sIqzA_0sMSLqGRO.
• Podcast interview for How on Earth with Joel Parker: https://howonearthradio.org/archives/10509
• San Diego, CA, live talk: Oct. 22, 4:30pm, Point Loma Library
• Berthoud, CO, live talk: Nov. 20, 7pm, Little Thompson Observatory

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Best,

Jeff