Sunlike stars hurl superflares about once a century
Our sun is a fairly peaceful star, only occasionally releasing flares powerful enough to spark auroras on Earth. But on December 12, 2024, researchers from the Max Planck Institute said that stars like the sun hurl superflares – flares with about 10,000 times the energy of a typical flare – approximately every 100 years. The scientists studied 56,000 sunlike stars and found this rate of about one superflare per star per century. What does that mean for our sun? According to the press release:
The sun, too, is likely capable of similarly violent eruptions.
The scientists published their peer-reviewed study in the journal Science on December 12, 2024.
What exactly is a superflare?
The sun produces flares all the time. If you read our daily sun news post, you’ll see the sun often produces mild C and M flares. And occasionally it fires off stronger X flares, especially around solar maximum, which is happening now. Solar maximum is the peak of the sun’s 11-year solar cycle. Sometimes strong flares can have an effect on Earth, like causing radio blackouts or triggering auroras.
One of the more powerful X flares the sun released in modern history was in 1859. Scientists estimate an X45 flare from the sun hit Earth and caused what’s now known as the Carrington Event. During that event, compasses failed to work, telegraph lines caught fire, and people saw auroras at far southern latitudes. But the new press release said about the Carrington Event:
According to estimates, the associated flare released only a hundredth of the energy of a superflare.
So superflares are more massive than anything we have experienced. They can contain energies of about 1034 ergs, which is equal to around a trillion hydrogen bombs.
More frequent superflares surprised scientists
We have limited data on how our star has behaved in the past. As co-author Sami Solanki of Max Planck Institute said:
We cannot observe the sun over thousands of years. Instead, however, we can monitor the behavior of thousands of stars very similar to the sun over short periods of time. This helps us to estimate how frequently superflares occur.
So by looking at 56,450 sunlike stars with the Kepler space telescope from 2009 to 2013, it was like looking at evidence of 220,000 years of stellar activity. The scientists found 2,889 superflares on 2,527 of the stars they studied.
The new study suggests that previous studies significantly underestimated the eruptive potential of sunlike stars. Previous studies estimated these flares would occur less frequently, on intervals of 1,000 to even 10,000 years. Lead author Valeriy Vasilyev of the Max Planck Institute said:
We were very surprised that sunlike stars are prone to such frequent superflares.
They were surprised because scientists have looked for but not found evidence of superflares affecting Earth. They’ve studied tree rings and ice cores, and while indeed they have found past signs of extreme solar events, they’ve fallen short of a superflare. One of the biggest events they’ve found yet occurred 14,300 years ago, according to the radiocarbon found in ancient tree rings. That one was about 10 times as strong as the Carrington Event. But superflares could still be about 100 times stronger than a Carrington Event.
That still doesn’t mean our sun hasn’t had a superflare in the more recent past. It just might not have expelled a blast of sun-stuff – a coronal mass ejection – at Earth to cause the imprint scientists look for.
When will our sun have a superflare?
The study does not predict when our sun might experience a superflare. But if these sunlike stars are truly representative of our sun, then it’s important we keep an eye on its activity. As the paper said:
If the sun behaves like the stars in this sample, then it could produce superflares at a similar rate.
Monitoring the sun and forecasting potential incoming storms is more important than ever. Today’s technology relies heavily on satellites that would be vulnerable in a strong geomagnetic storm. Satellite operators could take precautions to keep the harmful effects to a minimum. ESA’s upcoming space probe, Vigil – planned for 2031 – will watch the sun from the side to provide more of an advanced warning of incoming sun-stuff.
Co-author Natalie Krivova of the Max Planck Institute said:
The new data are a stark reminder that even the most extreme solar events are part of the sun’s natural repertoire.
Bottom line: Scientists studied thousands of sunlike stars and determined that they hurl superflares – massive solar flares – about once every 100 years.
Source: Sun-like stars produce superflares roughly once per century
The post Sunlike stars hurl superflares about once per 100 years first appeared on EarthSky.
from EarthSky https://ift.tt/75lGeai
Sunlike stars hurl superflares about once a century
Our sun is a fairly peaceful star, only occasionally releasing flares powerful enough to spark auroras on Earth. But on December 12, 2024, researchers from the Max Planck Institute said that stars like the sun hurl superflares – flares with about 10,000 times the energy of a typical flare – approximately every 100 years. The scientists studied 56,000 sunlike stars and found this rate of about one superflare per star per century. What does that mean for our sun? According to the press release:
The sun, too, is likely capable of similarly violent eruptions.
The scientists published their peer-reviewed study in the journal Science on December 12, 2024.
What exactly is a superflare?
The sun produces flares all the time. If you read our daily sun news post, you’ll see the sun often produces mild C and M flares. And occasionally it fires off stronger X flares, especially around solar maximum, which is happening now. Solar maximum is the peak of the sun’s 11-year solar cycle. Sometimes strong flares can have an effect on Earth, like causing radio blackouts or triggering auroras.
One of the more powerful X flares the sun released in modern history was in 1859. Scientists estimate an X45 flare from the sun hit Earth and caused what’s now known as the Carrington Event. During that event, compasses failed to work, telegraph lines caught fire, and people saw auroras at far southern latitudes. But the new press release said about the Carrington Event:
According to estimates, the associated flare released only a hundredth of the energy of a superflare.
So superflares are more massive than anything we have experienced. They can contain energies of about 1034 ergs, which is equal to around a trillion hydrogen bombs.
More frequent superflares surprised scientists
We have limited data on how our star has behaved in the past. As co-author Sami Solanki of Max Planck Institute said:
We cannot observe the sun over thousands of years. Instead, however, we can monitor the behavior of thousands of stars very similar to the sun over short periods of time. This helps us to estimate how frequently superflares occur.
So by looking at 56,450 sunlike stars with the Kepler space telescope from 2009 to 2013, it was like looking at evidence of 220,000 years of stellar activity. The scientists found 2,889 superflares on 2,527 of the stars they studied.
The new study suggests that previous studies significantly underestimated the eruptive potential of sunlike stars. Previous studies estimated these flares would occur less frequently, on intervals of 1,000 to even 10,000 years. Lead author Valeriy Vasilyev of the Max Planck Institute said:
We were very surprised that sunlike stars are prone to such frequent superflares.
They were surprised because scientists have looked for but not found evidence of superflares affecting Earth. They’ve studied tree rings and ice cores, and while indeed they have found past signs of extreme solar events, they’ve fallen short of a superflare. One of the biggest events they’ve found yet occurred 14,300 years ago, according to the radiocarbon found in ancient tree rings. That one was about 10 times as strong as the Carrington Event. But superflares could still be about 100 times stronger than a Carrington Event.
That still doesn’t mean our sun hasn’t had a superflare in the more recent past. It just might not have expelled a blast of sun-stuff – a coronal mass ejection – at Earth to cause the imprint scientists look for.
When will our sun have a superflare?
The study does not predict when our sun might experience a superflare. But if these sunlike stars are truly representative of our sun, then it’s important we keep an eye on its activity. As the paper said:
If the sun behaves like the stars in this sample, then it could produce superflares at a similar rate.
Monitoring the sun and forecasting potential incoming storms is more important than ever. Today’s technology relies heavily on satellites that would be vulnerable in a strong geomagnetic storm. Satellite operators could take precautions to keep the harmful effects to a minimum. ESA’s upcoming space probe, Vigil – planned for 2031 – will watch the sun from the side to provide more of an advanced warning of incoming sun-stuff.
Co-author Natalie Krivova of the Max Planck Institute said:
The new data are a stark reminder that even the most extreme solar events are part of the sun’s natural repertoire.
Bottom line: Scientists studied thousands of sunlike stars and determined that they hurl superflares – massive solar flares – about once every 100 years.
Source: Sun-like stars produce superflares roughly once per century
The post Sunlike stars hurl superflares about once per 100 years first appeared on EarthSky.
from EarthSky https://ift.tt/75lGeai
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