From: physnews@aip.org (AIP listserver)
Subject: PHYSICS NEWS UPDATE #222 (04/17/95)
A CIRCUMSTELLAR DUST RING has been observed by the Cosmic Background
Explorer (COBE) satellite during its survey of the sky. Computers'
simulations of the motion of asteroidal dust particles moving toward the
sun had shown that the presence of the Earth helps to trap some of the
particles in a circumsolar ring in which the Earth is embedded; the
disposition of dust would be denser beyond the Earth's orbit than inside
of it. Previously, the "zodiacal light" (reflected sunlight) from the
dust had been seen by the Infrared Astronomical Satellite (IRAS), but
COBE's observations are fuller and more unequivocal.
(W.T. Reach et al., Nature, 6 April 1995.)
INTERGALACTIC MAGNETIC FIELDS are probably very weak but
may well influence galaxy formation. These fields might be
primordial or might arise from magnetized plasma expelled by
galaxies. R. Plaga of the Max Planck Institute in Munich, Germany
suggests that the fields between the galaxies can be detected through
their influence on gamma ray bursts reaching the Earth. According to
Plaga, fields as weak as 10**-24 gauss would delay the arrival of
some gamma-ray photons by a measurable amount. He believes that
it might be possible to extract such information from gamma-burst
data of the type recorded by the Gamma Ray Observatory. (Nature,
30 March 1995.)
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- T o d d E. V a n H o o s e a r -
``'''vanhoose@lalaland.cl.msu.edu - vanhoose@msu.edu - vanhoose@lalaland.cl.msu.edu
(._.) Michigan State University - East Lansing, MI USA
(_) Computer Laboratory - Department of Communication
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