nearby supernova

The shocking discovery that the universe is expanding at a faster and faster rate has taken the 2011 Nobel Prize in physics. Three American-born astrophysicists will divide the $1.5 million prize, announced October 4 in Stockholm.


The discovery turned the world of physics and astronomy on its head when it was first reported in 1998 by competing teams of scientists, two from the United States and one from Australia.

It helped lead scientists to the conclusion that nearly three-fourths of the universe is made up of “dark energy,” a mysterious force that seems to be staying gravity’s hand in stopping the universe from expanding forever.

“By comparing the brightness of distant, far-away supernovae with the brightness of nearby supernovae,” Botner continued, “the scientists discovered that the far-away supernovae were about 25 percent too faint. They were too far away. The universe was accelerating. And so this discovery is fundamental and a milestone for cosmology. And a challenge for generations of scientists to come.”

The reason why this expansion is accelerating is still unexplained but the mystery gave rise to the theory of dark energy, a kind of intense gravity which seems to comprise up to three quarters of the universe.



Composite Image of the Tycho Supernova Remnant X-ray: NASA/CXC/SAO, Infrared: NASA/JPL-Caltech; Optical: MPIA, Calar Alto, O.Krause et al.