July 2026: Astro Letters

We say the Crab Nebula was born in 1054, but it actually was created 6,500 years before that. Credit: NASA, ESA, J. Hester and A. Loll (Arizona State University)

Nebulous age

In the Ask Astro column of the April 2026 issue is a photograph of planetary nebula NGC 6302. The caption says that NGC 6302 lies about 3,800 light-years away and is a relatively young nebula at about 2,200 years old. What am I missing? How did the light from a 2,200-year-old nebula traverse 3,800 light-years to get to us, seemingly 1,600 years early? — Daniel Stewart, Lakewood, Colorado

Hear Senior Editor Alison Klesman’s answer (or read it below):