title: Helium on venus: implications for uranium and thorium.
abstract: Helium is removed at an average rate of 10(6) atoms per square centimeter per second from Venus's atmosphere by the solar wind following ionization above the plasmapause. The surface source of helium-4 on Venus is similar to that on Earth, suggesting comparable abundances of crustal uranium and thorium.
authors.forename: M J
authors.initials: MJ
authors.lastname: Prather
authors.forename: M B
authors.initials: MB
authors.lastname: McElroy