American Physical Society meeting
Gas sheds light on dark matter, plus cosmic ray clusters and blue-light imaging in the news
By Science News
American Physical Society April Meeting, Anaheim, Calif., April 30–May 3
Gas map A 3-D map of gas in the far reaches of the universe could shed new light on dark matter. Using a 2.5-meter telescope with a wide field of view, Anže Slosar of Brookhaven National Laboratory in New York collected light from 14,000 bright, distant objects called quasars. Just as the moon illuminates clouds at night, quasar light reveals clouds of hydrogen gas in space, Slosar reported May 1. By mapping out variations in the density of this gas, he hopes to learn more about the universe’s expansion 10 billion to 12 billion years ago — and the role of dark energy in accelerating this expansion. — Devin Powell Cosmic ray hotspots Detectors buried in ice at the South Pole have revealed hotspots in the cosmic rays striking the Earth’s atmosphere. These small-scale patterns, spotted by the IceCube Neutrino Observatory and presented April 30, are similar to patterns previously seen in the Northern Hemisphere. Marcos Santander of the University of Wisconsin–Madison says that the source of these high-energy rays is unknown, but he’s looking for pulsars or distortions of the Earth’s magnetic field that could explain the observations. — Devin Powell Beta bluers Flashes of blue light seen in nuclear reactors may help scientists develop better medical imaging and cancer therapies. Physicists have long known that charged particles moving faster than the speed of light within a particular medium can give off this Cerenkov radiation. Now computer simulations developed by Nicole Ackerman of Stanford suggest that beta emitters, potential cancer treatments, also emit Cerenkov light in the body. The light doesn’t travel far through tissue. But it could be useful for watching drug candidates at work in animals or spotting tumors near the surface of the body, Ackerman reported. — Devin Powell