Catch a failing star: the tense wait for a supernova, Supernovae

If we looked at a star 10 billion light years away, wouldn't that star actually be dead by now even though we can see it as if it was alive? - Quora

If we observe a star that is 1.2 billion light years away explode, does it mean that the star exploded 1.2 billion years ago? - Quora

Supernova - Wikipedia

How quickly does a supernova happen?

Supernova - Wikipedia

Supernovae The Schools' Observatory

Going 'Nova: The Dying Breaths of a Star, by Robert Lea, The Cosmic Companion

Waiting for Betelgeuse to Explode - The New York Times

To catch a supernova

Core collapse supernova – Exoplanet Exploration: Planets Beyond our Solar System

If Betelgeuse goes boom: How DUNE would respond to a nearby supernova