Number 97, October 6, 1992 by Phillip F. Schewe and Ben Stein|
THE MOST DISTANT BODY IN THE SOLAR SYSTEM YET OBSERVED , an object called 1992 QB1, lies at a distance of 42 astronomical units (3.9 billion miles) from the Sun. Reported on Sept. 14, 1992 by David Jewitt (Hawaii) and Jane Luu (UC Berkeley), 1992 QB1 is estimated to be about 20 times larger than Comet Halley. If its trajectory around the Sun proves to be circular (several more months of observations are needed), astronomers may deduce that it comes from the Kuiper belt, the hypothetical ring of icy bodies (possibly remnants of the solar system's formation) beyond the outer planets. If, however, the trajectory proves to be parabolic, then 1992 QB1 may well have originated in the so called Oort cloud, an even more distant hypothetical staging area for long-period comets. If so, 1992 QB1 would present quite a spectacle for earthly observers by the middle of the next century, according to Brian Marsden of the Harvard/Smithsonian Center for Astrophysics. (Science News, 25 Sept.)
NIELSBOHRIUM, HESSIUM, AND MEITNERIUM are to be the names of elements 107, 108, and 109, respectively. All three were discovered in the 1980s at the Institute of Heavy Ion Research in Darmstadt, Germany, which is naming the elements after Niels Bohr, the German state of Hessen, and Lise Meitner. (Nature, 17 Sept. 1992.)
DIAMOND-FILM SEMICONDUCTOR devices may someday surpass silicon-based devices for speed and be able to operate at high temperatures. Scientists can now grow diamond films by planting tiny diamond seeds in a silicon wafer pocked with pyramidal pits. The pits line up the seeds' facets to within a fraction of a degree so that a subsequent low-pressure epitaxial laying down of atoms results in a nearly-single-crystal sheet of diamond (with sizes up to an inch in diameter). Doped with boron, the diamond film is semiconducting and can operate without breaking down at higher levels of voltage, power, and temperature (up to 700 C) than silicon or gallium-arsenide. This suggests that diamond circuits could be smaller and therefore faster. Device applications must await improvements in the ability to grow larger films. Also problems in etching circuit patterns and in controlling impurities must be overcome. (Scientific American, October 1992.)
1990-91 GRADUATE STUDENT SURVEY . A report released in July 1992 by the AIP Education and Employment Statistics Division indicates that the number of the physics graduate students in the U.S. was 14,065. Of these 1264 received PhDs at the end of the 90/91 year. Among PhD recipients, 11% were women and 40% were foreigners. The two leading areas of specialization among new PhD's were condensed matter physics (35%) and particle physics (18%). For the same period, astronomy departments had 880 graduate students and awarded 73 PhDs. Among the PhDs, 16% were women. (For more information, contact Susanne Ellis at AIP, 212-661-9404.)
SCIENCE SECTIONS IN MANY NEWSPAPERS have been discontinued. Only 44 weekly science sections remain from among a high of about 95 only a few years ago, according to a survey by the Scientists' Institute for Public Information (SIPI). Editors cited the poor national economy as the cause for the cutbacks.