NASA's solar observation satellite Interface Region Imaging Spectrograph (IRIS) has provided scientists with new information about the Earth's primary source of energy, the sun.
IRIS has observed nanoflares and plasma bombs on the sun, among other phenomena, which offered scientists new insights about the sun. The findings were published in five separate studies in the special Oct. 17 issue of the journal Science.
Hardi Peter, from the Max Planck Institute for Solar System Research in Germany, who led the team that analyzed the data on hot plasma bombs said that large amounts of energy released when the sun converts magnetic energy into thermal energy heat up pockets of plasma up to 180,000 degrees Fahrenheit in cooler surface regions. Peter said that the pockets explode like bombs spewing out superheated plasma. The plasma that moves upward likely disperses into the corona while the plasma that goes downward cools back.
"The hot plasma is heated by "bombs" in which the reconnection of magnetic fields leads to rapid heating. These unexpected results will likely lead to a reassessment of other phenomena in the low solar atmosphere, such as the mysterious Ellerman bombs discovered almost a century ago, " wrote Allan Title, from the Institute of Theoretical Astrophysics in Norway, and colleagues in "Probing the solar interface region," which introduced the special issue.
The IRIS also showed how high energy particles that are produced by nanoflare events influence the chromosphere, which together with the corona, make up the sun's outer atmosphere.
"The accelerated electrons deposit a sizable fraction of their energy in the chromosphere and transition region (TR)," wrote Paola Testa, from the Harvard-Smithsonian Center for Astrophysics , and colleagues, who conducted the study on the phenomenon based on the observations of IRIS. "Our analysis provides tight constraints on the properties of such electron beams and new diagnostics for their presence in the nonflaring corona."
In a statement, the U.S. space agency said that the new information would allow scientists to better understand how the Solar System's star transfers energy through its atmosphere, as well as track solar activities that can affect the technological infrastructure on Earth and in space.
NASA scientist Jeff Newmark, from the U.S. space agency's Heliophysics Division, also said that the findings suggest that the sun is more complex than previously believed.
"These findings reveal a region of the sun more complicated than previously thought," Newmark said. "Combining IRIS data with observations from other Heliophysics missions is enabling breakthroughs in our understanding of the sun and its interactions with the solar system."
