"Unlike the Earth's relatively quiet sun, Kepler 438 emits strong flares every few hundred days, each one stronger than the most powerful recorded flare on the sun.
During November 4 – 7, 1997, a series of strong flares occurred that were magnetically well-connected.
Thus, their plots revealed that for strong flares, especially X class, the β values were the same during all solar cycle conditions, while their H′ values were also seen to be same for any class of solar flares.
Our results also show greater differences in the values of β and H′ for strong flares in comparison with weak flares under both low- and moderate-solar activity conditions.
Thus, it can be inferred that strong flares, especially M and X class, can increase the D-region electron density and the redistribution of electron density with height more during low-solar activity conditions, lowering the D-region ionosphere when it is very sensitive, than during higher-solar activity periods.
The solar ionization variability consist mainly from the 11-year solar cycle, the 27-day solar rotation and solar flares, strong flares being very important phenomenon in the daytime lower ionosphere due to the enormous increase of the solar X-ray flux resulting in temporal terminating of MF and partly LF and HF radio wave propagation due to heavy absorption of radio waves.
"The most common arguments against habitability are tidal lock-ing, strong stellar magnetic fields, strong flares and high ultraviolet and X-ray fluxes; but none of these have been proved definitive".
Historically speaking, there are strong flares and plenty of auroras on Earth at the end of the solar peak, as particles from the sun strike our planet's magnetic lines and excite gases in the upper atmosphere.
Earth-like planets would have to orbit even closer to such stars and would thus suffer from stronger flare activity than the hypothetical planet in this study.
