On April 5, 2010, the sun spewed a two million-mile-per-hour stream of charged particles toward the invisible magnetic fields surrounding Earth, known as the magnetosphere. As the particles interacted with the magnetic fields, the incoming stream of energy caused stormy conditions near Earth. Some scientists believe that it was this solar storm that interfered with commands to a communications satellite, Galaxy-15, which subsequently foundered and drifted, taking almost a year to return to its station.
To better understand how to protect satellites from intense bursts of energy from the sun, scientists study the full chain of space weather events from first eruptions on the sun to how the magnetic fields around Earth compress and change shape in response. During the April 5 storm, two NASA Heliophysics System Observatory missions – the Interstellar Boundary Explorer (IBEX) and two spacecraft called the Two Wide-Angle Imaging Neutral-Atom Spectrometers (TWINS) – were perfectly positioned to view the storm from complementary viewpoints.
The three sets of instruments have been used together to paint a more complete picture of what happens during a solar storm, from initial impact of solar energy through to the particles that ultimately slide down into Earth’s atmosphere near the poles. These results were published online on March 27, 2012 in the Journal of Geophysical Research.
“One spacecraft can only take recurring measurements along its own flight path,” says Natalia Buzulukova, one of the authors on this paper and a geospace scientist at NASA’s Goddard Space Flight Center in Greenbelt, Md. and at the University of Maryland in College Park. “But this is not always enough to understand the whole event. With several spacecraft at once we have a unique opportunity to observe more of the magnetosphere simultaneously.”
The two TWINS spacecraft and IBEX orbit Earth in very different paths. TWINS travels along a highly elliptical orbit around Earth through the magnetosphere. IBEX, too, circles Earth, but generally lies outside the magnetosphere allowing it to map the very edges of the solar system. Together, they offer glimpses from the inside and outside of the magnetosphere, including the side that faces the sun, the side that extends long away from the sun – the magnetotail — and an electric current that sometimes appears around Earth like a giant hula hoop called the ring current…..
Read more: http://www.nasa.gov