Rare 'superflares' could one day threaten Earth

Rare ‘superflares’ could one day threaten Earth
An artist's depiction of a superflare on an alien star. Credit: NASA, ESA and D. Player

Astronomers probing the edges of the Milky Way have in recent years observed some of the most brilliant pyrotechnic displays in the galaxy: superflares.

These events occur when , for reasons that scientists still don't understand, eject huge bursts of energy that can be seen from hundreds of away. Until recently, researchers assumed that such explosions occurred mostly on stars that, unlike Earth's, were young and active.

Now, new research shows with more confidence than ever before that superflares can occur on older, quieter stars like our own—albeit more rarely, or about once every few thousand years.

The results should be a wake-up call for life on our planet, said Yuta Notsu, the lead author of the study and a visiting researcher at CU Boulder.

If a superflare erupted from the sun, he said, Earth would likely sit in the path of a wave of high-energy radiation. Such a blast could disrupt electronics across the globe, causing widespread black outs and shorting out communication satellites in orbit.

Notsu will present his research at a press briefing today at the 234th meeting of the American Astronomical Society in St. Louis.

"Our study shows that superflares are rare events," said Notsu, a researcher in CU Boulder's Laboratory for Atmospheric and Space Physics. "But there is some possibility that we could experience such an event in the next 100 years or so."

Scientists first discovered this phenomenon from an unlikely source: the Kepler Space Telescope. The NASA spacecraft, launched in 2009, seeks out planets circling stars far from Earth. But it also found something odd about those stars themselves. In rare events, the light from distant stars seemed to get suddenly, and momentarily, brighter.

Researchers dubbed those humongous bursts of energy "superflares."

Close to home

Notsu explained that normal-sized flares are common on the sun. But what the Kepler data was showing seemed to be much bigger, on the order of hundreds to thousands of times more powerful than the largest flare ever recorded with modern instruments on Earth.

And that raised an obvious question: Could a superflare also occur on our own sun?

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

To find out, Notsu and an international team of researchers turned to data from the European Space Agency's Gaia spacecraft and from the Apache Point Observatory in New Mexico. Over a series of studies, the group used those instruments to narrow down a list of superflares that had come from 43 stars that resembled our sun. The researchers then subjected those rare events to a rigorous statistical analysis.

The bottom line: age matters. Based on the team's calculations, younger stars tend to produce the most superflares. But older stars like our sun, now a respectable 4.6 billion years old, aren't off the hook.

"Young stars have superflares once every week or so," Notsu said. "For the sun, it's once every few thousand years on average."

The group published its latest results in May in The Astrophysical Journal.

Notsu can't be sure when the next big solar light show is due to hit Earth. But he said that it's a matter of when, not if. Still, that could give humans time to prepare, protecting electronics on the ground and in orbit from radiation in space.

"If a occurred 1,000 years ago, it was probably no big problem. People may have seen a large aurora," Notsu said. "Now, it's a much bigger problem because of our electronics."


Explore further

Kepler satellite telescope reveals hundreds of superflares on distant stars

More information: Yuta Notsu et al. Do Kepler Superflare Stars Really Include Slowly Rotating Sun-like Stars?—Results Using APO 3.5 m Telescope Spectroscopic Observations and Gaia-DR2 Data, The Astrophysical Journal (2019). DOI: 10.3847/1538-4357/ab14e6
Journal information: Astrophysical Journal

Citation: Rare 'superflares' could one day threaten Earth (2019, June 11) retrieved 22 August 2019 from https://phys.org/news/2019-06-rare-superflares-day-threaten-earth.html
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Jun 11, 2019
No 'could' needed here: Its a matter of when.
The Carrington event of 1859 and the Similar solar storm of 2012 (which missed a direct hit by only a few days) will happen again.
Its been estimated a hit would have cost around a trillion dollars in the US alone. And take years to recover from lost ground and satellite tech including GPS.
https://en.wikipe..._of_2012


Jun 11, 2019
I wonder if battery-powered EVs could be affected electronically by a super-duper solar flare.
All commerce, transportation and communications including the internet would stop dead.
Best to find protected residency in underground caves and a way to get there in the event, and stock up on candles and firewood/matches, a source of H2O and canned foods. I'd imagine that some very powerful radiation would reach Earth's surface, possibly causing wildfires and lakes to dry up.

Jun 11, 2019
I wonder if battery-powered EVs could be affected electronically by a super-duper solar flare.
All commerce, transportation and communications including the internet would stop dead.
Best to find protected residency in underground caves and a way to get there in the event, and stock up on candles and firewood/matches, a source of H2O and canned foods. I'd imagine that some very powerful radiation would reach Earth's surface, possibly causing wildfires and lakes to dry up.

This sounds like it may have happened around 12000 years ago... :-)
Another possibility...

Jun 11, 2019
The rare super flares is what the Suspicious Observers community has been referring to when discussing the Earth Catastrophe Cycle.
https://www.youtu...3APVS8br

Jun 12, 2019
The rare super flares is what the Suspicious Observers community has been referring to when discussing the Earth Catastrophe Cycle.
https://www.youtu...3APVS8br
says CD85

I've been watching several episodes starting with your link. Of course there is the possibility of "pole-shifts" occurring every so often. At least one of the episodes mention a 12000 yrs interval and that we are due for another one. But where is the relationship of Pole-shift with the Sun's SuperFlares. I don't think that extreme winds flowing around the Earth would cause a Pole-Shift.
A Pole-Shift would likely be caused by the molten iron in Earth's core flipping over and causing the mantles to slide in the same direction due to a magnetic field reversal, carrying the Earth's crust along with it. If I'm not mistaken.
I am not too sure that Velikovsky should have been mentioned in the video episodes, as he is not considered to be legitimate.

Jun 12, 2019
If a solar flare were powerful enough to kill electric cars, it would also kill gas cars; electronic ignition, don'cha know. Not to mention electronic fuel injection.

Jun 12, 2019
No 'could' needed here: Its a matter of when.
The Carrington event of 1859 and the Similar solar storm of 2012 (which missed a direct hit by only a few days) will happen again.
Its been estimated a hit would have cost around a trillion dollars in the US alone. And take years to recover from lost ground and satellite tech including GPS.
https://en.wikipe..._of_2012
I think you might have misunderstood the article. The Carrington event and the 2012 near miss were *not* superflares. They were coronal mass ejections, which are stronger than simple flares but are still hundreds to thousands of times weaker than superflares. The Sun has not had a superflare for as long as people have been observing it, since the ancient times.
If it will we are royally screwed - back to the Middle Ages. Flares and CMEs superflares are largely unidirectional, but the immense force and energy of the superflare would sweep almost the entire inner solar system.

Jun 14, 2019
But where is the relationship of Pole-shift with the Sun's SuperFlares. I don't think that extreme winds flowing around the Earth would cause a Pole-Shift.

These are two different concerns although the solar wind isn't just a wind.

A Pole-Shift would likely be caused by the molten iron in Earth's core flipping over and causing the mantles to slide in the same direction due to a magnetic field reversal, carrying the Earth's crust along with it. If I'm not mistaken.

The Earth's magnetic field isn't created by "a molten iron core" nor does the pole shift have anything to do with said molten iron.

I am not too sure that Velikovsky should have been mentioned in the video episodes, as he is not considered to be legitimate.

Velikovsky's legitimacy is challenged by acolytes protecting their cherished beliefs, that so many attack him for his research just goes to show how sadly pathetic his critics really are.

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