WASHINGTON, Sept. 29 — A burst of radiation from a distant star smashed into the Earth's upper atmosphere last month with
enough energy to power civilization for a billion billion years, astronomers say. The immense wave of energy, the most powerful ever
recorded from beyond the sun, caused at least two satellites to shut down briefly.
DESPITE ITS powerful beginnings, the wave of energy reached the Earth's surface at a strength equal only to a typical, single
dental X-ray. “We've been monitoring things like this for 30 years and we've never seen anything like this before,” Kevin Hurley, a
research physicist at the University of California, Berkeley, said Tuesday at a NASA news conference.
OVER PACIFIC OCEAN The burst of gamma and X-ray radiation struck the Earth over the Pacific Ocean at night on Aug. 27 and
was so powerful that it temporary ionized the upper atmosphere just as the sun does in the daytime, said Hurley. Seven scientific
satellites, five in orbit of the Earth, one approaching an asteroid far beyond, and one near the orbit of Jupiter, all detected the
massive eruption. Hurley said the burst was so intense that two of the satellites were forced to shut down to protect their
electronics. However, the energy was largely absorbed by the upper atmosphere and only a minuscule amount of radiation reached
the Earth's surface. It posed no hazard to life, Hurley said.
NEUTRON STAR THE SOURCE The eruption came from a neutron star, called SGR1900+14 in the constellation Aquila some
20,000 light years away. A neutron star is the collapsed core left after a massive star explodes. A light year is about 6 trillion miles.
Astronomers said it is extremely rare for such a distant stellar explosion to have any effect on Earth, attesting to the immensity of
the energy release. They estimated that the energy, if captured and put to use, could power all of the Earth's energy needs for a
billion billion years - that is one billion periods of one billion years. “In this five-minute long flash we saw as much energy as there
will be coming from the sun for the next 300 years,” said Hurley. “If we could harness this energy we would have enough power to
power every city, every village, every light bulb until the end of the universe and far beyond.” The source star already was being
studied because it is one of four known members of a class of stellar objects called “soft gamma ray repeaters.” These are neutron
stars that put out steady flashes of gamma rays. But the extreme energy burst last month also suggests the object is a magnetar,
a weird type of star first suggested by astrophysicists Robert Duncan of the University of Texas, Austin, and Christopher Thompson
of the University of North Carolina, Chapel Hill.
SAMMY SOSA OF ASTROPHYSICS The dramatic proof of the star's existence, said Cornell University astronomer Jim Cordes, “is
a triumph for theoretical astrophysics.
“This is the Sammy Sosa and Mark McGwire of astrophysics,” Cordes added. “It is that big a deal.” “It (the discovery) is that big.”'
Duncan said at the news conference that magnetars are rapidly spinning neutron stars that have created a magnetic field far greater
than any other known. He said the magnetic field around the star is so powerful that from more than 100,000 miles away “it could
erase the magnetic strip on your credit card and suck the keys out of your pocket.” Duncan said the energy burst probably occurred
when the magnetic field ripped apart the one-mile thick metal crust of the star, releasing an immense eruption of X-rays and gamma
rays. This radiation is not optically visible, but it can be detected by instruments on satellites. Magnetars are extremely dense
objects, containing one and a half times the mass of the sun in an area just 12 miles across, he said. “A tablespoon of material
from this star would weigh as much as an aircraft carrier,” said Duncan. Approaching a magnetars would not be healthy, the
astronomer noted. X-rays erupting from the star would kill from a distance. As one got closer, there would be lethal levels of
electrons and anti-electrons, in addition to immense heat. It is not, said Duncan, “a good place to go.”
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