All the winners of this year's Nobel Prizes in science!

The 2011 Nobel Prizes have been announced, honoring preeminent achievements in the fields of physics, chemistry, medicine, literature, the promotion of peace, and economics. Here's what you need to know about the three science-related Nobel Prizes.

Nobel Prize in Physics

The physics prize has been divided among three scientists, with half going to Saul Perlmutter of the Supernova Cosmology Project at Berkeley and the other half split between Brian P. Schmidt at the Australian National University and Adam G. Riess at Johns Hopkins, both of whom are members of the High-z Supernova Search Team. Even by the standards of the Nobels, these three are being honored for a towering achievement in physics: the 1987 discovery that the expansion of the universe is accelerating. This finding has radically redefined our understanding of the cosmos, and we're still struggling to come to grips with the driver of this expansion, the mysterious dark energy.

For more from the Nobel Committee, check out the physics page here. You can also check out the personal research pages of Saul Permutter, Brian P. Schmidt, and Adam G. Riess.

Nobel Prize in Chemistry

This year's chemistry prize goes to Dan Shechtman of the Israel Institute of Technology for the discovery of quasicrystals. Though quasicrystals aren't as famous as dark energy, they're every bit as controversial, as the Nobel committee explains:

On the morning of 8 April 1982, an image counter to the laws of nature appeared in Dan Shechtman's electron microscope. In all solid matter, atoms were believed to be packed inside crystals in symmetrical patterns that were repeated periodically over and over again. For scientists, this repetition was required in order to obtain a crystal.

Shechtman's image, however, showed that the atoms in his crystal were packed in a pattern that could not be repeated. Such a pattern was considered just as impossible as creating a football using only six-cornered polygons, when a sphere needs both five- and six-cornered polygons. His discovery was extremely controversial. In the course of defending his findings, he was asked to leave his research group. However, his battle eventually forced scientists to reconsider their conception of the very nature of matter.

Scientists have since accepted the existence of quasicrystals and found both naturally occurring and artificial examples of this exotic structure, which manages to be both regular and non-repeating. For more on Shecthman's work, check out the Nobel site, and his own research page is found here.

Nobel Prize in Physiology or Medicine

The last of the three science Nobels has also been divided among three researchers, with one half split between Bruce A. Beutler of the Scripps Research Institute and Jules A. Hoffmann of France's National Center of Scientific Research and the other half awarded to the recently deceased Ralph M. Steinman, formerly of Rockefeller University. Steinman, who died just three days before his prize was awarded, sadly becomes just the fourth person to receive a posthumous Nobel, as generally all laureates must still be alive. The Nobel committee believed Steinman was still alive when they awarded him the prize, and they have subsequently decided that the prize "was made in good faith" and that he keeps his posthumous honor.

Their work all focused on the immune system, with Beutler and Hoffman working on the activation of innate immunity while Steinman discovered the dendritic cell and how it fit into adaptive immunity. Here's the announcement from the Nobel Committee:

This year's Nobel Laureates have revolutionized our understanding of the immune system by discovering key principles for its activation.

Scientists have long been searching for the gatekeepers of the immune response by which man and other animals defend themselves against attack by bacteria and other microorganisms. Bruce Beutler and Jules Hoffmann discovered receptor proteins that can recognize such microorganisms and activate innate immunity, the first step in the body's immune response. Ralph Steinman discovered the dendritic cells of the immune system and their unique capacity to activate and regulate adaptive immunity, the later stage of the immune response during which microorganisms are cleared from the body.

The discoveries of the three Nobel Laureates have revealed how the innate and adaptive phases of the immune response are activated and thereby provided novel insights into disease mechanisms. Their work has opened up new avenues for the development of prevention and therapy against infections, cancer, and inflammatory diseases.

For more, check out the Nobel Prize in Medicine webpage here. You can also check out the Bruce Buetler Laboratory and Jules Hoffmann's page at the CNRS.

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