Astronomer Adam Riess, of the Space Telescope Science Institute and the Johns Hopkins University, and two colleagues, have been awarded this year's $1 million Shaw Prize in astronomy for their discovery of the mysterious "dark energy" that is causing the universe to expand at an ever-faster rate.
This is the third year for the Shaw Prize, awarded annually in three fields: astronomy, life science and medicine, and mathematical sciences. The prize was established by Run Run Shaw, a philanthropist and longtime leader in the Hong Kong film and television business. This year's presentation ceremony will be held Sept. 12.
Co-winners of the 2006 astronomy prize with Riess are Saul Perlmutter of the Lawrence Berkeley Laboratory of the University of California, Berkeley, and Brian Schmidt of the Mount Stromlo Observatory of the Australian National University in Canberra. Riess and Schmidt were leaders of one team that pursued the difficult and challenging measurements that led to the dark energy discovery in 1998. Perlmutter was the leader of a competing team.
Using a certain class of supernovae as distance indicators, the teams set out to measure the expansion rate of the universe in the past and compare it with the expansion rate of the present universe. They expected to find the universe slowing down under gravity, like a ball rolling up an incline. Instead, they were startled to find that the expansion rate is speeding up.
This implies that empty space has energy in it and that this energy is acting repulsively and accelerating the expansion of the universe. A century ago, Albert Einstein theorized such a force to keep the universe in dynamical balance. Once it was discovered that the universe is expanding, Einstein dismissed his idea that such a force actually existed.
Riess and his colleagues are working to determine the behavior of dark energy. Is it truly constant as imagined by Einstein, or changing over time? Riess is using NASA's Hubble Space Telescope and ground-based telescopes to continue characterizing the nature of dark energy. Because dark energy makes up 70 percent of the universe, it will have a profound influence on the universe's future evolution.
The 36 year-old astronomer has been at STScI since 1999. From 1996 to 1999, he was a Miller Fellow at the University of California, Berkeley. Riess is a 1992 graduate of MIT. He was awarded a doctorate in astrophysics from Harvard University in 1996.