Number 59, December 18, 1991 by Phillip F. Schewe and Ben Stein
SOME QUASARS PRODUCE ONE-SIDED JETS , streams of radio-emitting plasmas that can extend for hundreds of light years and propagate at apparently faster-than-light speeds. The favored theory explains these features, and the lack of a jet propagating in the opposite direction, by supposing that jets are produced on both sides of the quasar but that relativistic effects diminish the appearance of the receding jet (almost to nothingness) and distort the appearance of the on-coming jet so as to suggest superluminal velocities. New radio measurements of the jet from quasar 3C273 by a team of astronomers from Jodrell Bank (UK) and Caltech bear on this theory in two respects. (1) The apparent superluminal motion of the jet has in this case been established out to a distance of 400 light years from the quasar core, in keeping with the theory's insistence on relativistic speeds for the whole length of the jet column (previous jet studies had only established superluminal motion over tens of light years). (2) The non-appearance of a receding jet was measured to an unprecedented degree, to less than 1 part in 5300 of the brightness of the approaching jet. (R.J. Davis, Nature, 5 Dec. 1991.)
METAL-FILLED BUCKYBALLS in a variety of types were reported at the recent meeting of the Materials Research Society in Boston. A Naval Research Lab group, using laser light to open up fullerene molecules, was able to insert one or more yttrium atoms. At UCLA scientists created C-80 molecules containing two lanthanum atoms each. Meanwhile, an IBM researcher produced C-82 fullerenes containing lanthanum, scandium, or yttrium atoms. These findings are the first independent confirmations of Richard Smalley's demonstration of metal-filled fullerenes this past summer. (Science News, 14 Dec. 1991.)
A DISTANT CLOUD OF CARBON MONOXIDE gas, estimated to be 12 billion years old, was discovered by astronomers at Kitt Peak. Since cosmologists believe that only hydrogen and helium were produced during the Big Bang, this finding indicates that stars---manufacturers of the heavier elements such as carbon and oxygen---formed, exploded, and then spewed out their elements as early as 3 billion years after the creation of the universe. Since the gas cloud was detected in an amorphous lump interpreted as an undeveloped galaxy, it also presents the possibility that the birth of stars predates galaxies. (Science News, 7 Dec. 1991.)
CONTINENT-SIZED WINDSTORMS have been detected in the mesosphere, a little-studied region of the atmosphere at an altitude of 30 to 60 miles above the earth's surface. Paul B. Hays of the University of Michigan, speaking at last week's meeting of the American Geophysical Union in San Francisco, described data recorded in November 1991 by the NASA Upper Atmosphere Research Satellite. He and his colleagues observed vortices of air as big as the U.S. swirling about at velocities as great as 200 miles per hour.
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