The Fermi Gamma-Ray Telescope from NASA identified the highest energy light ever connected with a solar eruption during the powerful March 7 solar blast.
The discovery represents Fermi's operation as a solar observatory that investigates solar outbursts at the time of the sun's maximum period of activity.
A solar flare is an explosive discharge of charged particles and light. The X5.4 classification flare on March 7 is the most intense eruption observed by Fermi's Large Area Telescope (LAT) thus far. The flare produced a blast of gamma rays and the sun appeared so bright across the gamma-ray sky.
Fermi's solar studies were presented by Omodei during the 220th meeting of the American Astronomical Society in Anchorage, Alaska.
During the solar flare's peak, the LAT identified gamma rays with 2B x the energy of visible light, or around 4 B electron volts (GeV). The flux of high-energy gamma rays having energies that exceed 100 M electron volts (MeV) was 1,000 x more than the sun's steady output.
The March flare is significant due to the persistence of its gamma-ray emission. The high-energy gamma rays were detected using Fermi's LAT for a record time of 20 h.
Furthermore LAT's keen angular resolution enabled localizing a greater than 100-MeV gamma-ray source to the sun's disk. The entire sky can be scanned every 3 hours using Fermi's LAT. It can detect gamma rays with energies ranging from 20 MeV to over 300 GeV.
The Gamma-ray Burst Monitor (GBM) is another Fermi instrument that can scan the entire sky unblocked by the Earth. It can detect light at energies from 8,000 eV to 40 MeV.
Both instruments were used to observe a solar flare on June 12, 2010, which was powerful, but less intense.
As the sun advances toward the peak of its 11-year-long activity cycle, solar eruptions are forecasted during mid-2013.
Source: http://www.nasa.gov/