I've just finished reading
Measuring the Universe by Kitty Ferguson. It's a laymans guide to the history and techniques that have been used to measure the universe, starting with Erastothenes attempts to measure the earth's circumfrence, through the works of Copernicus and Galileo to how modern day science can know the universe is as big as it is.
It's a fascinating and well written read containing plenty of interesting trivia even for those with a decent science background while being simple enough that (I suspect) pretty much anyone could understand it. The only real drawback being the relative lack of detail on how
exactly the more modern techniques work.
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