(CN) — Modern understanding of ancient solar storms has allowed scientists to pinpoint exactly when Vikings were in North America. And that year happens to be 1021 — a millenium ago.
Were the Norsemen here any other year? Did they stay several years? Possibly. But analysis of the remains of wooden tools used by Europeans from the L'Anse aux Meadows site in northern Newfoundland shows they were here that year.
Prior to this discovery, scholars only had a general idea of when the Vikings were in North America. Nailing down an exact year may begin a new age of scientific analysis of the Viking presence in North America, said Michael Dee, a geoscientist at the University of Groningen in The Netherlands, who is one of the leaders of the project. They published their findings Wednesday in the journal Nature.
"If we can start getting more and more exact results like this, and couple it with new scientific technologies, we can understand how long they were there," he said. "History is only understood by [knowing] exactly when things happen and then getting them in order and putting them in relation to one another," he said.
Scientists have discovered that solar storms throughout history have boosted the amount of radiocarbon in the atmosphere the year they occur, that radiocarbon is absorbed by trees through photosynthesis, and that radiocarbon can be found in the ring of a tree for that year.
This means if a scientist was to split apart a tree and count its rings, they could identify the specific year for that ring using radiocarbon dating. The same thing is true for the the wooden handle of an ancient tool. And thanks to a solar storm, there was an update in radiocarbon production in the years 992 and 993 A.D.
This led Dee, Margot Kuitems, also of of the University of Groningen, and other scientists to investigate if it was possible to determine a year for when the Vikings were in North America.
L'Anse aux Meadows was identified as a Viking settlement in 1960. A husband and wife team relying on old Norse sagas located the site, finding iron nails and other artifacts that could not have come from local indigenous people, according to a 2015 article in JSTOR daily. Kuitems visited L'Anse aux Meadows, and went through artifacts there.
Scientists studied three wooden artifacts from the site, each from three different trees, that been cut with metal blades — a material not used by indigenous people. The number of rings in each artifact from the solar-storm year added up to 1021.
"It could have been any year but it just happened to be that year," Dee said.
A.J. Timothy Jull, a geoscientist at the University of Arizona, said radiocarbon dating normally gets you within 30 or 40 years of an object's age.
"They were able to date it to one year, which of course dates the object," said Jull, who was not involved in the project but is familiar with it. "This is a big development."
Jull said the technique has been used elsewhere. The specific year of construction of a Swiss church was recently dated to the 700s after its roof beams were studied.
Dee said that the discovery also leads to more questions. Any king of any country in Europe probably would have been informed of the Viking adventures in North America, he said. What does that tell us about the explorations of Christopher Columbus — who claimed to have sailed around Iceland when he was younger — and other Europeans nearly five centuries later?
"This just shows us what we don’t know and actually once we piece it all together we might have a different picture altogether," Dee said. "I think there’s a lot to be learned.”
Read the Top 8
Sign up for the Top 8, a roundup of the day's top stories delivered directly to your inbox Monday through Friday.