For example if the Betelgeuze system had a planet, with a theoretical large telescope on that planet and looked back at earth. It would see life and civilizations from the 15th century a.d. (~500 light years distance)
For example if the Betelgeuze system had a planet, with a theoretical large telescope on that planet and looked back at earth. It would see life and civilizations from the 15th century a.d. (~500 light years distance)
https://www.goodreads.com/book/show/382161.Chindi
Awesome, thank you :)