Math Puzzle for September 4, 2026

August 27, 2026: Phoebus and Phoebe have it out at 12:13 PDT

Alameda Post - A math diagram of an eclipse. The distance that one of the solar bodies peeks out from the other is distance d.

Lunar eclipses occur when the Earth’s umbra is cast onto the moon’s surface. Measured at the moon, the Earth’s umbra has a diameter of 9200 kilometers. However, the moon has a diameter of only 3474 kilometers. Much of the Earth’s umbra passes by the moon, into deep space and far beyond.

The U.S. west coast witnessed a “blood moon” eclipse on August 27, 2026. Technically, sanguinity aside, it was a deep-partial lunar eclipse. Measured in Ashland, Oregon, the umbra covered 95.8713046% of the moon’s surface. Only a thin crescent or sliver of the moon was visible above the umbra.

Assuming that the event was two-dimensional or coplanar, find the distance d.

A correct answer sent to [email protected] could win a Tucker’s gift card.

Last week’s winner was Lian Wong with an angle measure of 23 degrees.

(Use of AI to solve this problem is strictly prohibited.)

Jeff Smith is a former Math teacher and a retired US Navy Lieutenant Commander. Reach him at [email protected].

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