May 16
Solarballs got it wrong: Sun's birth cluster
So, since the show started out as educative I thought it was worth mentioning this:
The Alpha Centauri System wasn't near the Sun when it formed.
Stars move at different speeds through the galaxy, and so, the Alpha Centauri System is our neighbour NOW, but it wasn't back then and won't be in the future. Same can be said of Arcturus.
The one that could really have been there was the old star, that I think it's meant to be Coatlicue. Its supernova was the one that supposedly triggered the formation of the Sun and some sibling stars (aka stars from its birth cluster) by compressing the cloud of gas that would form them.