There are many seminar series that Graduate students can benefit from attending.
For First and Second Year Graduate students the Friday Afternoon Seminar series, which is supported by the department, but organized by the students is an excellent venue for meeting potential research advisors.
All graduate students and faculty should attend the Colloquium on Tuesdays at 4:15 in Harriman 137, this is a great way to stay up to date with the latest advances in all areas of Physics and Astronomy. Also we serve cookies, coffee and tea from 3:45!
A full list of departmental seminars can be found here.