In recent days, NASA’s SDO (Solar Dynamics Obersavatory) space probe detected and documented 3 M-class solar flares, the class that includes the most powerful ones after the X-class, where X means “eXtreme”. The first one had its peak on April 2 at 8.02 UTC, the second one at 20.33 UTC and the third one on April 3 at 14:29 UTC.
The SDO probe is in fact a space telescope specialized to study the Sun. Launched in February 2010, from its geosynchronous orbit it keeps an eye on solar activity with its instruments to allow scientists to study everything about the Sun. Together with other ground-based and space telescopes, SDO is also used to monitor solar flares, storms that can be very violent.
The Earth is protected by its magnetic field that acts as a shield preventing the solar radiation from causing damage on the ground, unless it’s an extreme flare such as the Carrington Event of 1859, which generated an aurora seen even in the sky over Cuba and above all created big problems to the telegraph network, then the most advanced technology in the world.
No more flares with energies comparable to the Carrington Event have been detected but the increasing amount of electronic equipment, electrical grids that power them and even more so the many satellites in orbit can be vulnerable to class-M flares too.
A measure of the energy generated in the flare provides more information along with its class. The class M is about one tenth of the intensity of the class X. The M2 class has twice an intensity of the M1, the M3 three times and so on. The recent days flares were classified respectively as M5.3, M5.7 and M5.8. In short, those were three quite intense flares.
Luckily the consequences reported were limited with some radio blackout. NOAA (National Oceanic and Atmospheric Administration) reported type R2 blackouts in a scale in which R1 is the minimum level and R5 is the maximum level, which means that the recent days blackout wasn’t anything serious.
The monitoring of the Sun is continuous but at the moment in the case of a class-X flare we wouldn’t be very prepared for its consequences. The USA is investing heavily in new, even more advanced, space probes that might allow to better understand the dynamics of solar activity. The ultimate goal is to prepare for the worst to avoid devastation that would cripple the electrical systems in the world.