Last year scientists found evidence of unusually high levels of radioactivity occurring in the late eighth century. Radioactive carbon in ancient Japanese trees and high levels of radioactive isotopes in the ice of Antarctica were two indicators that the Earth was hit by a massive burst of radiation in 774 or 775 C.E. What caused this remarkable spike? Professor Ralph Neuhauser, leader of a research team at the University of Jena, credits it to an explosive cosmic bang -- possibly the collision of two neutron stars or black holes.
Yet medieval folk would have been unaware of the event, because it would not have been visible to the naked eye.
But Gamma-ray bursts are exceedingly rare -- so rare, in fact, that the likelihood of them being the cause of this radiation spike is practically nil. Solar flares might be responsible.
Find out more in these articles:
- Did an 8th Century Gamma Ray Burst Irradiate Earth?
Article at Science Daily.
- Gamma-ray burst 'hit Earth in 8th Century'
Feature by Rebecca Morelle at BBC News.
- Gamma-ray burst, most powerful type of explosion in universe, may have hit Earth in 8th century
Article by Zenaira Ali at the National Post.
- Gamma-ray burst blasted Earth in 8th century
Item at Cosmos Magazine.
- 'Powerful' gamma ray burst may have 'hit Earth in 8th Century'
Article at ZeeNews.
- 8th-century tree rings hint at close-range space blast
Item by Jacob Aron at New Scientist.
- Massive Cosmic Explosion 'Struck Medieval Earth'
Article by Michael Rundle at the Huffington Post.
- Did cosmic collision flood medieval Earth with gamma rays?
Feature by Emma Woollacott at TG Daily.