I gave a lecture on Cepheids and the distance ladder this morning. Obviously I showed this picture, pointed to Polaris, and explained that foreground contamination can often be a significant source of systematic errors. 🔭

RArichardalexander.bsky.socialOct 10, 2024 9:15pm

Managed to grab a few pictures of the #auroraborealis (near Nottingham) before it clouded over. 😀 🔭

Ha. One man's noise, etc..