The information on graduate programs in the school of science is available in this link. Applicants for the Department of Astronomy are requested to submit each copy of Official Score Report and Examinee’s Score Record of the GRE General Test.
It is required that applicants contact faculty members they hope to be supervised before the submission of the application. Here is the list of the faculty members. Questions on the admission procedures and the programs should be sent to the admission office of the School of Science (see individual programs given in http://www.s.u-tokyo.ac.jp/en/admission/) or to your candidate supervisor.