I was on SAS flight 944 (SK944) from Chicago USA to Copenhagen DK when I saw this on the live aurplsne tail cam. It was about 1.5 hours before landing. The flight left on December 28th from Chicago and landed at 10:07 am on December 29th. I confirmed with the pilot after the flight that he also saw it, although I didn’t catch the exact coordinates (have an approximation). We were likely somewhere just north of the Shetland islands or a bit further west towards the Faroe Islands. https://www.flightaware.com/live/flight/SAS944