Visitors to the Google homepage (www.google.com) were greeted with a doodle showing equations for quantum mechanics, with the tip indicating Bohr's 127th birth anniversary.
As in the past, clicking on the doodle will take the visitor to a Google Search Results page for "Niels Bohr."
"In addition to his major contributions to theoretical physics, Bohr was an excellent administrator. The institute he headed is now named for him, and he helped found CERN, Europe's great particle accelerator and research station," the US Public Broadcasting Service said.
Bohr was born Oct. 7, 1885 in Copenhagen, Denmark.