Astronomers formed a new method for predicting solar flares using data from the Solar Dynamics Observatory (SDO). The research team from NorthWest Research Associates identified small flashes in the sun’s corona that could be a precursor for flares.
The flashes could indicates when and where the flares occur. They typically occur in the lower layers of the corona called the photosphere and chromosphere. Previously, astronomers could only watch areas of greater sunspot activity, which indicated areas of greater magnetic activity on the sun’s surface.
“We can get some very different information in the corona than we get from the photosphere, or ‘surface’ of the Sun,” said KD Leka, lead author on the new study who is also a designated foreign professor at Nagoya University in Japan. “Our results may give us a new marker to distinguish which active regions are likely to flare soon and which will stay quiet over an upcoming period of time.”
The research team used SDO’s recently generated image database of the Sun’s active regions. The images were taken in the ultraviolet and extreme-ultraviolet light spectrum over a period of eight years. Data from the Atmospheric Imaging Assembly (AIA) on SDO can be easily used for large statistical studies.
Predicting flares is important because they can disrupt space-based assets in Earth orbit and pose a potential threat to astronauts on missions like the typically 5- to 6-month increments on the International Space Station or future crewed Artemis lunar missions.
Orbiting satellites provide services ranging from Internet access and television broadcasts to critical navigation services through GPS. If you subscribe to a TV service like DISH Network, you probably rely on satellites to get your favorite live sports events. Modern navigation apps like Google Maps rely on GPS, which powers a billion-dollar industry that also includes GPS golf rangefinders and navigation systems for boats.
Solar flares could have serious effects for military assets, as well. The United States Navy revived celestial navigation as an alternative in case GPS satellites get wiped out by a solar flare or cyberattack.
Most modern weather forecasts also rely on weather satellites, which make them more accurate by providing real-time data on weather systems. Weather reports for the Tampa Bay region in Florida rely on the weather satellite Klystron 9, for instance.
These are all assets that could be disrupted by a large enough solar flare aimed at Earth. Most recently, solar activity wiped out some Starlink satellites that had recently been launched. SpaceX’s Starlink satellites can provide Internet service to regions that don’t have many good options for reliable Internet access. Because Starlink already has thousands of satellites in low-Earth orbit and SpaceX frequently launches more of them, the loss was only a minor setback. However, it was a minor demonstration of how serious solar flares can be.
Solar flares can pose a threat to astronauts by exposing them to high levels of radiation. This can increase the risk of cancer and other health problems. Radiation has already been a high concern for space agencies like NASA because any potential future crewed missions to other worlds like the Moon or Mars will take astronauts outside of the protective Van Allen belts, which ward off most radiation by trapping charged particles in Earth’s magnetic field.
Especially intense auroras are typically caused by high levels of solar activity that sent out high levels of charged particles to be trapped by the Van Allen belts. This prevents the charged particles from reaching the surface to cause damage to life on Earth’s surface.
Better predictions of high levels of solar activity that could cause flares could help protect orbiting satellites and astronauts on long-duration missions by providing enough warning for them to get “under cover,” either by adjusting their orbits or getting them into a shelter designed to protect them from radiation – or, in the case of astronauts on the International Space Station, getting them back to Earth if necessary.
The NorthWest Research Associates research team published their findings in The Astrophysical Journal. They say their new model for predicting solar flares is the first in a series of papers examining the chromospheric and coronal properties of solar active regions.