It appears that our Sun could be capable of producing a “superflare”, which is a mysterious phenomenon that was discovered by the Kepler space mission four years ago, according to researchers from the Aarhus University. They describe the possibility as “frightening”, since more modest Sun storms, with less power than a superflare, have affected the Earth in previous years.
Solar strikes often reach the Earth, when energetic particles are thrown away from the Sun into Space. When these eruptions interfere with our planet, they generate auroras. However, a different type of eruption called “superflares” that remain a mystery for the scientific community, could cause severe consequences to Earth.
It remained unclear whether the Sun could produce a superflare under the same mechanism it uses to produce a solar flare. An international team led by Christoffer Karoff, from Aarhus University in Denmark, suggests that possibilities are weak, but it is still not impossible.
The Sun has been described as a “dangerous neighbor”. A report published by the team in the journal Nature Communications mentions how a solar eruption of hot plasma reached the Earth in September 1859, creating an aurora and breaking down some radio communications.
That being said, there are stars in the solar system that produce eruptions (superflares) up to 10.000 times larger than the occurred in 1859, which are apparently produced like solar flares, says the team of researchers after analyzing data taken of thousands of stars, which were observed by the Kepler space telescope and the new Guo Shou Jing telescope in China.
“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” explains Christoffer Karoff.
The Sun can effectively create a superflare
Results would appear to show that the sun is too weak to produce a superflare. However, the team has determined that the magnetic field of 10 percent of all the observed superflares have the same or similar strength than the magnetic field of the Sun
“We certainly did not expect to find superflare stars with magnetic fields as weak as the magnetic fields on the Sun. This opens the possibility that the Sun could generate a superflare – a very frightening thought” says Christoffer Karoff in a press release.
Even when possibilities do not appear significant, if an eruption of the size of a superflare reaches the Earth’s atmosphere, it could have disastrous consequences for the environment and ecosystems.
It appears that a superflare struck the Earth in AD 775.
Researchers have analyzed geological archives and found rests of radioactive isotope C formed in the Milky Way, which means that a small superflare could have reached the Earth’s atmosphere in AD 775. As a result, they propose that the Sun should produce a small superflare every millennium.
This theory was developed after analyzing the spectrum and magnetic fields of more than 100,000 stars since the Guo Shou Jing telescope allowed the team to obtain data of up to 4,000 stars at the same time, researchers explained in a report.
Source: Aarhus University
http://scitech.au.dk/aktuelt/deadly-stars/