Arthur B. McDonald of Queen's University in Canada and Takaaki Kajita of the University of Tokyo were awarded Nobel Prize for making a groundbreaking discovery in physics.

The prize committee announced the names of the winners on Tuesday. The project led by the Canadian scientists, deep inside a nickel mine near Sudbury, Ontario, was assisted by the University of Pennsylvania.

The team including several hundreds of researchers and technicians included more than a dozen from Penn. These researchers helped design and develop high-tech particle detectors and also analyzed the results.

The findings collected by both the Canadian and Japanese groups revealed that neutrinos, which were earlier thought to be mass-less, actually have some mass.

Scientists said with some further research on neutrinos and their subatomic kin, they expect they will be able to improve their understanding of such cosmic mysteries as exploding stars and the formation of the universe.

The prize will be awarded in Stockholm on December 10 to Arthur B. McDonald, who led the project in the nickel mine, and Takaaki Kajita of the University of Tokyo, who led experiments in a Japanese zinc mine.

The neutrinos were detected in the Canadian mine by measuring their interactions with molecules of ‘heavy’ water, in a giant plastic tank built 6,800 feet beneath the surface.

Penn physics professor Josh Klein, one of the team members, said he has spent almost his two years going deep into the mine for almost eight to 10 hours every day.

The air pressure that far beneath the surface is noticeably higher, said fellow Penn physics Professor Eugene Beier, also part of the team.

"It's something that you don't do with a stuffed-up head," Beier said.

"I think he would be the first to say that the result was the product of the work of many dedicated and talented people," Klein said.