Starship Asterisk*

Thanks for the info. There is enough concensus among the replies to assist my very rusty physics knowledge. I can understand what's going on.

I am wondering why all galaxies have a circular disc shape and are not sperical in shape. Also, I understand that the search for exoplanets uses the technique of watching stars for a slight dimming if/when a planet passes between the star and the observer. Does this mean that only those stars whose ...