If youโ€™ve spent any time reading nerdy blogs or pop-science books, you probably know that outer space isnโ€™t just made up of nothing. Thereโ€™s something out there called dark that makes up a massive percentage of the big inky absence. Youโ€™re actually being bombarded with dark matter particles as you read this. The Cosmic Cocktail: Three Parts Dark Matter is physics professor Katherine Freeseโ€™s guide to dark matter, from the story of its discovery to possible future applications of this research. Youโ€™ll never look at the void between stars in the same way again. (Town Hall, 1119 Eighth Ave, townhallseattle.org, 7:30 pm, $5)