Tabby's Star

A star dimming in impossible patterns. "Megastructure" made it into the papers.

KIC 8462852: Kepler photometry showed irregular dimming to 22% — no known planet or dust model fit cleanly, and a century of archival plates suggested long-term fading. Astronomer Jason Wright floated the megastructure hypothesis in the literature, and SETI pointed the Allen Array at it within weeks. Subsequent multi-band observation (dimming is wavelength-dependent) points to dust, and the field considers it closing. The file remains as precedent: for one season, 'alien megastructure' was a respectable sentence in an astronomy paper, and the protocols for taking such a signal seriously got their first rehearsal.