Powerful superflares could pose a threat to Earth



"More accurate evaluations of the effects of superflares is a next urgent task", Notsu told Astronomy, "but we can now expect things such as large-scale blackouts, satellite communication failure, and strong radiation in space", which can do serious damage to instruments and astronauts alike.

Astronomers first observed signs of these powerful superflares thanks to NASA's now-retired Kepler space telescope.

Our Sun may be middle-aged but it still has the energy to expel superflares, a rare rush of energy, every few thousands of years that could destroy Earth's spacecraft and electronics, scientists warned.

Unfortunately, the researchers say it is not possible to predict when our sun will produce a superflare. An artist's depiction above of a superflare on an alien star. However, upon unleashing the superflare, the L dwarf star briefly shone 10,000 times brighter than normal, making it an easy target for a number of ground based and orbital observatories.

According to the latest reports coming from Express.co.uk, researchers at the University of Colorado Boulder (CU Boulder) in the USA are now fearing that older and quieter stars like our Sun can produce these blasts.

Scientists dubbed these events "superflares" - and, as it remains unclear exactly how they are triggered, have wondered whether they ever take place on our local star, the Sun.

If a superflare erupted from the sun, he said, Earth would likely sit in the path of a wave of high-energy radiation.

Dr. Notsu said: "Our study shows that superflares are rare events". "But there is some possibility that we could experience such an event in the next 100 years or so".

Older stars like our Sun do so "once every few thousand years on average". But it also found something odd about those stars themselves. Flares are known to occur often on our Sun, and can last anywhere from minutes to hours at a time.

"When our sun was young, it was very active because it rotated very fast and probably generated more powerful flares", said Notsu, also of the National Solar Observatory in Boulder.

"It is unbelievable that such a puny star can produce such a powerful explosion", co-author Peter Wheatley, an astronomy and astrophysics professor at the University of Warwick and leader of the NGTS, said in the statement.

'But we didn't know if such large flares occur on the modern Sun with very low frequency'.

To understand more, Notsu's team ran new spectroscopic observations with Kepler data, also utilising data from the European Space Agency's Gaia spacecraft and the Apache Point Observatory in New Mexico. The researchers then subjected those rare events to a rigorous statistical analysis.

"We need more studies to clarify the properties of superflare stars on Sun-like stars and to answer the important question, 'Can our Sun have superflares?'" the team writes.

'If a superflare occurred 1,000 years ago, it was probably no big problem, ' Dr Notsu said, explaining that people may have seen a large aurora as a result of the event. "Now, it's a much bigger problem because of our electronics".

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