In the sun’s blazing upper atmosphere, a team of scientists has found new clues that could help predict when and where the next solar flare might explode.
Using data from NASA‘s Solar Dynamics Observatory, or SDO, researchers at NorthWest Research Associates, or NWRA, have identified small signals in the upper layers of the Sun’s atmosphere, the corona, that can help determine which regions on the Sun are more likely to produce solar radiation. eruptions energetic discharges of light and particles released from the Sun.
They found that over the regions about to ignite, the corona produced small-scale flashes like tiny sparklers before a large firework display. The information could eventually help improve predictions of flares and space weather storms disturbed conditions in space caused by solar activity.
Space weather can affect Earth in many ways: producing auroras, endangering astronauts, disrupting radio communications, and even causing major power outages.
Scientists have previously studied how activity in the lower layers of the Sun’s atmosphere such as the photosphere and chromosphere can indicate impending flare activity in active regions, which are often marked by sunspot clusters, or strong magnetic regions on the Sun’s surface, which are compared to darker and colder by its surroundings. New findings published in The Astrophysical Journal complete this picture.
KD Leka, lead author of the new study, who is also a designated visiting professor at Nagoya University in Japan said “We can get very different information in the corona than we get from the photosphere, or ‘surface,’ of the Sun, “Our results can give us a new indicator to distinguish which active regions are likely to flare up soon and which will remain quiet in the coming period.”
Sun captured by the SDO
For their research, the scientists used a newly created database of images of active regions of the Sun captured by the SDO. The publicly available source, described in a companion article also in The Astrophysical Journal, combines more than eight years of images taken of active regions in ultraviolet and extreme ultraviolet light.
A new database by the NWRA team led by Karin Dissauer and designed by Eric L. Wagner makes it easier for scientists to use data from the Atmospheric Imaging Assembly (AIA) at SDO for large-scale statistical studies.
Dissauer said “This is the first time a database like this is readily available to the scientific community and will be very useful for studying many topics, not just active regions ready to flare”.
The NWRA team studied a large sample of active regions from the database using statistical methods developed by team member Graham Barnes. The analysis revealed small flashes in the corona before each eruption. These and other new findings will allow researchers to better understand the physics going on in these magnetically active regions in order to develop new tools to predict solar flares.
Dissauer said “We’re really starting to dig deeper with this research,”Connecting all this information from the surface up through the corona should allow forecasters to better predict when and where solar flares will occur.”