A new study led by researchers from the Max Planck Institute of Solar System Research (MPS) has revealed stars like our sun emit a massive burst of energy called a “superflare” that can prove dangerous or evenly deadly roughly every 100 years, meaning our Sun’s next event is already overdue.
Previous research has suggested that superflares, which release more than one octillion joules of energy within a short period, may occur less frequently than once every millennium. However, new evidence gathered from thousands of sun-like stars suggests that our sun’s next event could happen at any time.
“The new data are a stark reminder that even the most extreme solar events are part of the Sun’s natural repertoire,” warned study co-author Dr. Natalie Krivova from the MPS.
When Was The Sun’s Last Superflare?
Since the dawn of the space age, scientists have been able to directly measure the amount of interstellar and solar radiation striking Earth’s atmosphere. During that time, they have not detected a solar event powerful enough to be classified as a superflare.
Without direct measurements, researchers have developed methods to study the amount of radiation impacting Earth at different times in the past. For example, an uncharacteristically powerful surge of solar particles colliding with the Earth’s atmosphere can leave traces of the radioactive carbon isotope 14C in tree rings and glacial ice.
When looking for this type of evidence, the researchers say they found five “extreme solar particle events” and three additional candidates within the past 12,000 years. If all eight are confirmed, the rate of such events would be around once every 1,500 years. The most violent of these solar particle events occurred in 775 A.D., suggesting that our sun’s next similar event may still be 200 years away.
Still, the researchers caution that the relationship between a superflare and these extreme solar particle events caused by coronal mass ejections is poorly understood. Based on their new research, that event could happen at any moment.
“It is unclear whether gigantic flares are always accompanied by coronal mass ejections and what is the relationship between superflares and extreme solar particle events,” explained study co-author Prof. Dr. Ilya Usoskin from the University of Oulu in Finland.
“This requires further investigation,” the professor added.
Studying Thousands of Sun-Like Stars Reveals Stark Timeline
Since the amount of data available on the sun only goes back so far, the researchers decided on a novel approach to determining when our sun’s next superflare may occur: They would study many sun-like stars instead.
“We cannot observe the Sun over thousands of years,” explained Prof. Dr. Sami Solanki, director of the MPS and the study’s co-author. “Instead, however, we can monitor the behavior of thousands of stars very similar to the Sun over short periods of time.” Solanki said that by comparing the number of flares witnessed at a set time to the number of sun-like stars observed, the team could devise a formula to help the team “estimate how frequently superflares occur.”
The effort started by analyzing data on 56,450 sunlike stars collected by NASA’s Kepler space telescope between 2009 and 2013. According to Prof. Dr. Alexander Shapiro from the University of Graz, this extensive catalog provided the team with evidence of 220,000 years of stellar activity.
After sifting through the data to remove potential error sources such as cosmic radiation, passing asteroids, comets, and even non-sun-like stars that are near enough to a target star to cause interference, the team began analyzing the images pixel by pixel to look for changes in brightness significant enough to indicate a superflare. This process discovered evidence of 2,889 superflares occurring on 2,527 of the 56,450 observed stars. According to a statement from the research team, this number means that, on average, a typical sun-like star produces one superflare “approximately once per century.”
“We were very surprised that sun-like stars are prone to such frequent superflares,” said the study’s first author, Dr. Valeriy Vasilyev, from the MPS.
Preparing for Potentially Deadly Consequences
In the study’s conclusion, the authors reaffirm that Earth scientists have not measured a superflare coming from the sun in the 70-plus years satellites have been operating in space. The scientists also say that due to the incomplete science on the relationship between evidence of extreme solar particle events and superflares, they may not know about the sun’s next superflare until it happens. Still, the consequences of a massive release of solar energy striking Earth can be significant.
In 1859, a gigantic solar storm dubbed the “Carrington Event” caused the entire telegraph network to collapse across large portions of North America and northern Europe. The team says the solar flare that caused that event released only a hundredth of the energy needed to be classified as a superflare. This means the consequences of a superflare on modern technologies, including computer networks and especially satellites, could be devastating. In the case of transportation technologies that rely on GPS and high-tech systems to coordinate traffic, the consequences of a powerful superflare could even be deadly.
Fortunately, the team says there are ways to prepare for a superflare. Starting in 2031, the European Space Agency’s Vigil probe will view the sun from the side, offering a much earlier warning for any such space weather event. With enough warning, satellites could be shut off for protection, and transportation authorities can warn pilots and drivers of potential system disruptions before failing systems result in tragic consequences.
The study “Sun-like stars produce superflares roughly one per century” was published in Science.
Christopher Plain is a Science Fiction and Fantasy novelist and Head Science Writer at The Debrief. Follow and connect with him on X, learn about his books at plainfiction.com, or email him directly at christopher@thedebrief.org.