According to an announcement of Dr. Harlow Shapley, Director of the Harvard College Observatory, last night, Dr. Richard Prager, lately of the University of Berlin and one of the leading European astronomers, will arrive in Boston tomorrow on the Samaria to join the research staff of the Harvard College Observatory. Research work on variable stars will keep him at Harvard for at least two years.

Dr. Prager, who was stationed until recently at the Berlin-Babelsberg Observatory, is an outstanding bibliographer in the large field of variable stars and was responsible for many years for naming variable stars and for recording them in the annual catalogue, Dr. Shapley said.

At the observatory Dr. Prager will join the Milton Bureau, an organization subsidized by the Milton Fund of the University, and the members of which are analyzing the light variations of the two or three thousand brightest variable stars and will before the conclusion of their study amass more than a million observations and record the behavior of these stars on photographs taken since 1885.