Question: what would happen if the sun in Alpha Centauri exploded and created a super nova would it effect us?

Guy Rixon answered on 8 Mar 2018:

Good question. Firstly, none of the stars in the alpha-Cen system are big enough to become supernovae, so it’s not actually going to happen (see https://en.wikipedia.org/wiki/Alpha_Centauri#Alpha_Centauri_A).

BUT if there were a supernova at that distance things on Earth would get “interesting”. The light isn’t enough to cook us, but the hard radiation – gamma rays – that comes of the supernova would interact with our atmosphere. It turns out that the gamma rays would wreck our ozone layer, so people would get ill from the solar UV light. See https://en.wikipedia.org/wiki/Near-Earth_supernova for more details.

Also, the radiation would *probably* (I don’t have a reference to confirm this) kill all the satellites in Earth orbit. That means no more satellite Internet-connections, no satellite TV and, significantly, *no GPS system for navigation*. We could fix all that with new satellites – the radiation burst lasts less than a day – but losing GPS for a few months would be very awkward. Consider: a lot of the food you eat, and almost all the manufactured goods like ‘phones and cars and fridges and such, comes to the UK on ships. The ships find their way here using GPS…