Check this out: There has been an influx of cosmic rays due to a number of things, the major reason being the shrinking of the heliosphere and the extended, never-before-seen inactive solar minimum the sun recently experienced.
So these cosmic rays come in, hit the earth's magnetic field, and get trapped between the twin Van Allen Belts and just bounce back and forth between the two, accumulating.
In 1992, between the months of August and November, they found that the amount of cosmic rays in this new 'raditation belt', DOUBLED.
Think of where it's at now!
Further, and you won't believe this, guess where the largest accumulation of these anomalous cosmic rays are trapped...
RIGHT ABOVE THE SOUTH ATLANTIC ANOMALY! It looks as if these accumulating, trapped, anomalous cosmic rays are generating the SAA's weaking magnetic field!
Headquarters, Washington, D.C.
May 25, 1993
(Phone: 202/358-0883)
Embargoed until Noon
Michael Finneran
Goddard Space Flight Center, Greenbelt, Md.
(Phone: 301/286-5565)
Jay Aller
California Institute of Technology, Pasadena, Calif.
(Phone: 818/356-3631)
RELEASE: 93-94
SCIENTISTS LOCATE NEW RADIATION BELT AROUND EARTH
The location of a radiation belt of cosmic rays -- particles from beyond the solar system -- has been pinpointed several hundred miles above the Earth, according to scientists from the California Institute of Technology, Pasadena, and NASA's Goddard Space Flight Center,Greenbelt, Md.
A NASA satellite called Solar, Anomalous and Magnetospheric Particle Explorer (SAMPEX), was orbiting 375 miles (600 kilometers) above the Earth when it measured the belt.
The belt is most intense above a 5,000-mile (8,050- kilometer) strip of Atlantic Ocean between the southern tips of South America and Africa, Caltech and NASA scientists said at the annual meeting of the American Geophysical Union in Baltimore, Md., on Tuesday, May 25.
The belt is composed of particles known as anomalous cosmic rays, which are the result of the sun's interaction with tenuous gas that exists between the stars in the Milky Way galaxy.
"We were pretty sure the belt was there, and now we've pinned it down along with its location, which we didn't know before," said Goddard's Dr. Tycho von Rosenvinge, a member of the SAMPEX team.
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The first clear evidence for such a radiation belt was discovered by a team of Russian and U.S. scientists in 1991 using information from a series of Russian COSMOS spacecraft.
They were unable, however, to determine directly the location of the belt, which is composed of different high-energy particles than another region of radiation, the Van Allen radiation belts discovered by James A. Van Allen in 1958 using data from NASA's Explorer 1 satellite.
The belt in which the anomalous cosmic rays collect is embedded within the inner of the two Van Allen belts. The geometry of these belts is determined by the Earth's magnetic field lines, which connect the North and South magnetic poles.
"The cosmic rays become trapped in this field, where they bounce back and forth between the poles of Earth's magnetic field," said Caltech's Dr. Richard Mewaldt, a member of the SAMPEX team along with Caltech colleagues Drs. Jay Cummings, Alan Cummings, Richard Selesnick and Edward Stone.
The rays are the most intense in the 5,000-mile (8,050- kilometer) strip between South America and Africa, Mewaldt said, because the Earth's magnetic field is not centered perfectly, and this is where it allows the trapped particles to get closest to the planet's surface.
SAMPEX scientists said trapped cosmic rays can be stored in the belt for weeks or more, so the intensity can build up over time as more arrive. More of the cosmic rays collect in the belt during periods of minimum solar activity, which follows an 11- year cycle.
The trapped radiation has doubled between August and November 1992, according to SAMPEX measurements, and now is about 100 times the intensity of the anomalous cosmic rays in interplanetary space.
"This long-term storage will give the SAMPEX team a unique opportunity to study the properties of interstellar matter right in Earth's back yard," Mewaldt said.
SAMPEX was launched in July 1992 on a Scout rocket from
Vandenberg Air Force Base, Calif. The satellite is managed by Goddard for the Office of Space Science at NASA Headquarters in Washington, D.C.
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