On Sept. 28, 2015, an intense solar flare exploded from a sunspot called Active Region 2422. According to Space.com, the medium-size M7-class flare knocked out low-frequency radio communications over South America and the Atlantic Ocean.
“A solar flare occurs when magnetic energy that has built up in the solar atmosphere is suddenly released,” according to NASA. “Radiation is emitted across virtually the entire electromagnetic spectrum, from radio waves at the long wavelength end, through optical emission to x-rays and gamma rays at the short wavelength end.”
Energy released from such events is equivalent to millions of 100-megaton hydrogen bombs detonating at the same time.
A team led by the Univ. of Warwick discovered a stellar superflare from a binary star in the Milky Way galaxy with similar wave patterns to solar flares from the sun, indicating the sun may be capable of such destructive outbursts.
The research was published in The Astrophysical Journal Letters.
Thousands of times more powerful than the solar flares recorded on the sun, the superflare comes from KIC9655129. Comparatively, such a superflare would be equivalent to around a billion megaton bombs.
“If the sun were to produce a superflare it would be disastrous for life on Earth; our GPS and radio communication systems would be severely disrupted and there could be a large scale power blackouts as a result of strong electrical currents being induced in power grids,” said Chloë Pugh, of the university’s Centre for Fusion, Space and Astrophysics.
The team employed a time series analysis on KIC9655129 to detect wave patterns in the flare’s light curve. The data used was collected from the NASA’s Kepler space telescope.
“When a flare occurs we typically see a rapid increase in intensity followed by a gradual decline,” said co-author Anne-Marie Broomhall. “Usually the decline phase is relatively smooth but occasionally there are noticeable bumps, which are termed ‘quasi-periodic pulsations’ or QPPs. We used techniques called wavelet analysis and Monte Carlo modeling in order to assess the periodicity and statistical significance of these QPPs.”
The team discovered the flare exhibited two independent periodicities, which indicates the QPPs were caused by magnetohydrodynamic oscillations, a common observation in solar flares. This finding “supports the hypothesis that the sun is able to produce a potentially devastating superflare,” said Broomhall.
However, Pugh said such a superflare is unlikely to occur based on the sun’s previous solar activity.