Number 199, October 19, 1994 by Phillip F. Schewe and Ben Stein
THE MOST DISTANT MOLECULAR GAS ever observed has been detected in quasar
H1413+117 at a redshift of 2.5 using telescopes in France and Spain. The
gas, carbon monoxide, actually sits in the host galaxy which surrounds
the quasar (nicknamed the cloverleaf quasar) and seems to constitute the
bulk of the galaxy. This observation is important since it helps to establish
an earlier point in the history of the universe at which a galaxy's mass
could still largely consist of molecular gas rather than condensed stars.
(Richard Barvainis et al., Nature, 13 October 1994.)
COSMIC-RAY NEUTRINOS are behaving strangely. Neutrinos are light (perhaps
massless) particles that interact so weakly that enormous detectors might
observe less than 100 of them in a year. Theorists estimate that among
neutrinos created in air showers caused by cosmic rays smashing into Earth's
atmosphere (neutrinos from the sun are another matter), muon neutrinos
should outnumber electron neutrinos by a ratio of 2 to 1. Instead, recent
measurements have turned up with a ratio more like 1 to 1. Such an anomalous
ratio has been reported by a number of labs, including Kamiokande in Japan,
Soudan in Minnesota, and the IMB detector in Ohio. Meanwhile, scientists
at the Frejus detector under the French Alps see no anomalous effect, while
yet another group, the MACRO team, working in the Gran Sasso tunnel under
the Apennine Mountains in Italy, see a smaller and more ambiguous anomaly.
Although short of being statistically conclusive, the data seem to indicate
a shortfall of muon neutrinos. The leading theoretical explanation for
this is the notion that neutrinos can transform ("oscillate")
from one type to another and that erstwhile muon neutrinos are being detected
as electron neutrinos. (Physics Today, Oct.)
INTERNET TRAFFIC FOR THE 1984-1994 DECADE amounted to 3 x 10**14 bytes,
half of that coming in the past year alone. To better accommodate future
needs, the principal conduit for this flood of data, the National Science
Foundation network, has just been restructured. According to Glenn Ricart
of the University of Maryland, a number of changes in Internet traffic
will result: (1) The price charged by the NSF network for participating
institutions will go up but, because of the economy of scale, the expected
price per usage should remain about the same. (2) Large institutions will
probably still continue to pay for service at a flat rate but others may
soon be billed by the byte. (3) Some institutions which formerly offered
network access to individuals outside their immediate user group as a public
service are now contracting or eliminating these services. Hereafter these
popular services might be underwritten by corporate sponsorship (like public
television) or made available through subscription. Ricart believes the
impact of these changes will be small at first but will increase through
the years: "The new Internet will not be free, but it is likely to
get your dollars or ECUs faster by attracting them than by extracting them."
(Computers in Physics, Sep/Oct 1994.)
THE EUROPEAN SYNCHROTRON RADIATION FACILITY (ESRF) , now in operation,
is the brightest laboratory source of x rays. The $600 million machine,
hosting about 2500 scientists per year, generates its x rays using a circulating
beam of 6-GeV electrons. A 7-GeV machine at Argonne and an 8-GeV machine
in Japan are currently under construction. (Science, 7 Oct.)
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