Number 5, October 18, 1990 by Phillip F. Schewe and Ben Stein
SUPERNOVA 1987A PULSAR: Brazilian astronomers have reported observing quasiperiodic optical pulsations from 1987A on September 17 and September 28. Astronomers believe that in the wake of supernova explosions pulsars (rapidly spinning neutron stars broadcasting light in a searchlight pattern) will often be formed. Last year a Berkeley group was mortified to discover that their sighting of a pulsar at 1987A was attributable to an electrical artifact in their equipment. The Brazilians, whose observations have not yet been confirmed, believe that the pulsar (if it is really there) is oriented with its pole toward the earth and that its pulsed radiation comes to us indirectly and intermittently by bouncing off intermediate dust material along the line of sight. (Nature, October 11, 1990.)
INDIUM-PHOSPHIDE CLUSTERS ,some containing only six atoms, have optical properties similar to those of InP in bulk form, according to scientists at AT&T Bell Labs. Owing to the fundamental structural differences between a collection of atoms locked in small (perhaps ringlike) clusters in a gaseous state and atoms sitting in a crystal, the absorption spectrum of the clusters should have been much different from that of the bulk material, but was actually very similar: both exhibit a continuum absorption band. The puzzled Bell Labs scientists are studying the effect of cluster size on the resultant spectra. (Physical Review Letters, 22 Oct.; contact Mary Louise Mandich, AT&T Bell Labs, 201-582-3396.)
THE OZONE HOLE OVER ANTARCTICA has reopened and is nearly as bad as in the worst years of 1987 and 1989. The depletion of stratospheric ozone, caused by man-made chlorofluorocarbons, allows more solar ultraviolet radiation to reach the earth's surface. (The New York Times, October 12, 1990.)
THE SUPERSTRING THEORY ,sometimes referred to as the "theory of everything" since it apparently unifies all four known forces into a single framework, has been criticized on the grounds that it is not testable. Now theorists Dimitri Nanopoulos of Texas A&M University and John Ellis of the CERN laboratory in Geneva, Switzerland assert that their version of the theory is open to experimental verification. In particular, they claim that soon they may be able to calculate the mass of neutrinos, or the lifetime of protons; they may be able to predict the existence of new particles not yet observed, including a new class of non-radiating particles, "cryptons," which, if they exist, might account for some of the "missing mass" in the universe. (Science News, October 13, 1990; Nanopoulos: 409-845-7790.)
THE AIP SCIENCE WRITING AWARD to a scientist has been given to Bruce Murray for his book, "Journey Into Space: The First Thirty Years of Space Exploration." Murray, formerly head of the Jet Propulsion Lab at Caltech, chronicles his involvement with numerous space missions and with government bureaucracy. (For more information, contact the AIP Public Information Division.)
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