Question: How big was the biggest star you have ever mapped?

Nick Wright answered on 16 Mar 2014:

The biggest star I have ever studied had the really exciting name of W26 and it had a diameter 1600 times larger than our Sun! This means that if you placed it where our Sun is it would swallow the Earth! Unfortunately our telescopes are not good enough to map the surfaces of stars like these at the moment, because even though they’re really big, they’re also far away. The star W26 is about 8,000,000,000 times further away from us than the Sun is! Which is luckily actually, because its so big and its also very bright!