A superflare from the sun could wipe out life on Earth, a new study reveals. Such an event could have dire consequences for our planet.
Solar eruptions frequently send streams of energetic particles toward the Earth, where they are deflected by the magnetic field of our home planet. This phenomenon can produce stunning displays of aurora, or polar lights, which may be seen from the surface of the Earth.
Superflares were first detected four years ago by astronomers using the Kepler space observatory to study distant stars. The mechanism behind this phenomenon is unknown to astronomers. If the process which produces these massive plasma-rich flares is the same as that seen creating normal flares on our sun, then our own star may be capable of producing the powerful eruptions.
In 1859, a massive eruption from the sun sent charged particles and plasma toward the Earth. When this energetic material reached our home planet, it created northern lights that could be seen as far south as Cuba. Telegraphs started to signal on their own even when disconnected from their network. This bizarre phenomenon became known as the Carrington Event.
Some of the superflares seen on other stars can be up to 10,000 times more powerful than the 1859 event in our own solar system. The magnetic fields around these stellar bodies were examined, and their strengths were compared to the presence of the superflares.
"The magnetic fields on the surface of stars with superflares are generally stronger than the magnetic fields on the surface of the sun. This is exactly what we would expect, if superflares are formed in the same way as solar flares," said Christoffer Karoff of the Aarhus University in Denmark.
Only about 90 percent of stars producing superflares were found to have magnetic fields stronger than the one surrounding our own sun. The remainder were the same strength, or even weaker, than that possessed by our local star. This finding suggests that even though a superflare emanating from the sun is unlikely, such a scenario is not impossible.
A superflare from the sun may have struck the Earth in the year 775 of the common era. Tree rings from that time show a sudden significant increase in concentrations of the radioactive isotope carbon 14. This isotope is produced by cosmic rays from space striking the atmosphere.
A similar event may have also taken place in the year 993, researchers report. Researchers determined the sun may emit one of these super-powerful flares once every 1,000 years, on average.
If such an event were to occur today, it could be devastating for modern electronics, and could destroy the ozone layer, threatening life all over the planet.
The analysis of superflares and how they may form on our own sun was published in the journal Nature Communications.
