File:Barack Obama greets Burton Richter and Mildred Dresselhaus

34 White house in may 2012 Images: PICRYL - Public Domain Media

President Barack Obama, right, greets Buzz Aldrin, left, Michael

Obama Honors Burton Richter with Prestigious Enrico Fermi Award

President Barack Obama awards the 2012 National Medal of Arts to

President Barack Obama awards Dr. Mark Humayun of the University

President Barack Obama awards Dr. Stanley Falkow of Stanford

Burton richter hi-res stock photography and images - Alamy

Barack obama oval office 2010 hi-res stock photography and images

President Barack Obama awards the 2010 Presidential Medal of

President Barack Obama, right, and Dr. Jill Biden, left, wife of

President Barack Obama awards the 2010 Presidential Medal of