Boom is etymologically related to Beam. Boom is a type of Grow. Mushroom is a type of Grow. Mushroom is a synonym of Mount. 
you are likely to find Radiation in/at/on Space. 
Beam <--EtymologicallyRelatedTo-- Boom --IsA--> Grow <--IsA-- Mushroom <--Synonym--> Mount 
Space <--AtLocation-- Radiation 