Number 87, July 6, 1992 by Phillip F. Schewe and Ben Stein
THE AMERICAN CENTER FOR PHYSICS , the new headquarters of the American Institute of Physics (AIP), The American Physical Society (APS), and the American Association of Physics Teachers (AAPT), will be located in suburban Washington, D.C. near the College Park campus of the University of Maryland, on a plot of land purchased on June 30, 1992. The 120,000 square-foot Center building, designed by the firm of Skidmore, Owings & Merrill, should be finished in the fall of 1993. While retaining its Woodbury, Long Island publishing facility and its marketing and advertising offices in New York City, AIP will shift to Maryland the bulk of its management structure, as well as such departments as Public Information, Physics Today, and the Center for the History of Physics. (For more information, contact the Director's office, AIP, 516-576-2211.)
A NEW MEASUREMENT OF THE COSMIC MICROWAVE BACKGROUND at frequencies of 10.45 and 14.9 GHz confirms the Cosmic Background Explorer (COBE) results and sets some new restrictions on theories describing the origin of the universe. At the ground-based Observatorio del Teide in Tenerife, Canary Islands, a British-Spanish team measured microwave radiation at intermediate angular resolutions (one measurement was on a 5.6 degree scale) covering a portion of the sky, as opposed to COBE, which measured the entire sky at angular scales between 7 and 180 degrees. The data of the Tenerife team set an upper limit for cosmic microwave temperature variations of 51 ľK on a 5-degree scale, consistent with COBE's detection of a temperature difference of 30 ľK on a 10 degree scale. The Tenerife results set constraints on models proposing variations in the density of dark matter and they reject inflationary models having a zero cosmological constant. In addition, the team did not detect the large fluctuations in temperature that cosmic strings or cosmic textures would generate. In the next year, the Tenerife team expects to increase the sensitivity of their measurements and also produce maps (instead of upper limits) of temperature fluctuations when it adds data from a third microwave frequency (33 GHz). (Nature, 25 June 1992.)
PLATE TECTONICS ON VENUS? In its recent mappings of Venus, the spacecraft Magellan seemed to rule out any global-scale plate tectonics on the planet, but some scientists re-analyzing its images believe that there may be local tectonic processes at work. At the Spring meeting of the American Geophysical Union in Montreal, Dan P. McKenzie of Cambridge University described his studies of Venusian coronas, quasicircular regions on the planet with volcanic activity below and deep troughs at the edges. He found that the 4600-km Artemis corona, located in a high-altitude equatorial region on the planet, has 4-km deep troughs with features resembling those of the Earth trenches where the sinking of crust takes place. Specifically, the trough surrounding Artemis has chasms whose edges have distinctive bulges resembling the shape that Earth trenches acquire when crust sinks into the Earth. The bulges may represent crust formed from cooled volcano lava sinking into the planet. However, evidence for this process has only been clearly found on Artemis, and this plate-tectonic like process may not occur on the smaller coronas on the planet. (Science, 19 June 1992.)
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