The University of Chicago Magazine

Cosmic rays illuminated

When astronomers first detected cosmic rays in 1963, they weren’t sure the discovery was real; possessing 100 million times the energy of the world’s most powerful particle accelerators, cosmic rays fly through space at the speed of light and regularly shower Earth with microscopic charged particles. But in the November 9 Science, the Auger collaboration—an international research team cofounded by Chicago physicist James Cronin, SM’53, PhD’55, and including nine other Chicago scientists—announced they’d discovered the source of cosmic rays: the brightly lit, violent cores of nearby galaxies. Fueled by supermassive black holes, these galactic nuclei are located in “the suburbs of the Milky Way,” says Chicago astrophysicist and Auger collaborator Angela Olinto. At the 1,200 square-mile Pierre Auger Observatory in Argentina, scientists detected and analyzed the highest-energy cosmic rays, those least disrupted by the earth’s atmosphere. Next they hope to discover what accelerates cosmic rays to such extreme energies.

Hoover-bill

Its head pointed downward, Nigersaurus grazed on prehistoric plants.

With a mouth like a vacuum cleaner, the dinosaur Nigersaurus taqueti roamed the African forest 110 million years ago grazing for ferns, horsetails, and other ground-level greenery, its head perpetually tilted toward earthward. In a November 21 Public Library of Science–ONE paper, Chicago paleontologist Paul Sereno and six coauthors describe the prehistoric herbivore as a Mesozoic cow. Its squared-off muzzle contained more than 50 tightly-lined columns of teeth that formed, in effect, a pair of scissors for mowing down plants. Among the Nigersaurus’s anatomical oddities was a backbone of paper-thin vertebrae. The first Nigersaurus bones were discovered in the 1950s by French paleontologists digging in Saharan Africa; Sereno’s team unearthed the skull bones there a decade ago.

Movie company

There may yet be a reason not to abandon the movie theater for the DVD player. In the December Journal of Consumer Research, GSB marketing associate professor Suresh Ramanathan and behavioral scientist Ann L. McGill, MBA’85, PhD’86, report that others’presence may enhance moviegoing experiences. In two separate studies—one in which viewers watched film clips either alone or with other viewers and charted their feelings from moment to moment using joysticks; and another in which the researchers videotaped participants and studied their faces for glances at seatmates—Ramanathan and McGill found film-related emotions to be contagious. Sitting together, viewers evaluated the films within the same “broad mood” and rated the film higher when their feelings aligned with those of others. But if, in the screen’s glow, they saw their neighbors express an emotion different from their own, the realization dampened their subsequent facial expressions.

Hands across the blackboard

Schoolchildren perform better at math when they use their hands to express themselves, reports psychologist Susan Goldin-Meadow and colleagues at Chicago, Northwestern University and the University of Rochester. In her latest research on the cognitive benefits of gesturing, Goldin-Meadow studied 176 third- and fourth-graders, randomly assigning them to groups told to gesture or not to gesture, or to a group told nothing at all. All were given six math problems to solve. The students encouraged to use their hands proved four times more likely than those given no instructions to manually express new ways to solve problems. And after a math lesson, the gesturing students calculated correct answers to 50 percent more problems than those asked to keep their hands still. The researchers published their findings in the November Journal of Experimental Psychology: General.