Daily Space Puzzle · archive

#40 Fri, 6 Nov 2026

One space question a day, the same for everyone in the world. Two tries. A new puzzle opens at 00:00 UTC.

From the archive (Fri, 6 Nov 2026). Today's puzzle is #41.

RocketsTwo tries

Specific impulse, a standard measure of rocket engine efficiency, is expressed in which unit?

Pick an answer. Wrong first time? You get one more try. The answer, its official source and where to read more appear when you finish.

Play any of them; only today's puzzle counts toward your streak. Every past puzzle

One space question a day, the same for everyone in the world. A new puzzle opens at 00:00 UTC. A puzzle you opened before midnight UTC still counts for its own day if you finish it after.
Two tries. Your result is 1/2 (first try), 2/2 (second try) or X/2 (missed), and the share grid shows only that, never the answer.
Every question was checked by hand against an official source (NASA, ESA, JAXA, NOAA, the UN and the like) on the date shown with the answer. Spotted a mistake? Tell us and we will correct it in public.
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