February 22, 2014
NASA’s IRIS Spots Its Largest Solar Flare Yet On January 28
[ Watch the Video: IRIS Spots Its Largest Solar Flare ]
April Flowers for redOrbit.com - Your Universe Online
Solar flares are bursts of X-rays and light that stream out into space, disrupting long-range radio transmission on Earth and satellite functions in space. What sets them off, however, is still a mystery for scientists.
With unprecedented resolution, IRIS gives NASA investigators a view into a layer of the sun's lower atmosphere just above the surface called the chromosphere. IRIS is unable to view the entire surface of the sun at one time, however, so the research team has to make decisions about what region might provide useful observations at what time.
A magnetically active region on the sun was observed on January 28, and IRIS was focused on it in order to allow the team to see how the solar material behaved under intense magnetic forces. At 2:40pm EST, IRIS observed a moderate flare, labeled an M-class flare, erupting from the area—sending light and X-rays into space. An M-class flare is the strongest class flare after X-class.
The sun's chromosphere is key to regulating the flow of energy and material as they move from the sun's surface out into space. During this transition, the energy heats up the upper atmosphere, or corona, which can power solar events such as this flare.
Aboard IRIS is a spectrograph — an instrument capable of separating out the light it sees into individual wavelengths. These wavelengths, in turn, correlate to material at different temperatures, velocities and densities. IRIS's spectrograph was aimed directly into the heart of the flare when it reached its peak. The data obtained from this observation will help scientists to determine how different temperatures of material flow, and give more insight into how flares work.
Lockheed Martin Solar and Astrophysics Laboratory manages the IRIS mission, while NASA's Ames Research Center is responsible for missions operations and ground data. The Pleiades supercomputer housed at Ames was used to carry out many of the numerical simulations that are led by the University of Oslo.