The sun, the singular source of energy for our planet, also occasionally sends its curses, in the form of coronal mass ejections — warning against which is one of the purposes of India’s Aditya L-1 mission.
CMEs — ejections of charged particles — are a daily occurrence that is taken care of by the earth’s magnetic field, but sometimes the storm overwhelms the magnetic field.
Scientists have discovered that one particularly brutal CME happened 14,300 years ago — from the remnants of a tree!
When particles from the sun interact with the earth’s atmosphere, they create carbon-14 or radiocarbons, which are absorbed by trees.
A team of British and French scientists (rather serendipitously) discovered an unprecedented amount of radiocarbon while analysing semi-fossilised tree rings in the Alps, according to a press release from the University of Leeds. Staring at it in disbelief, they turned to ice cores from Greenland for confirmation, measuring beryllium content in the cores.
A similar solar super-storm today could wipe out telecommunications, satellite systems and electricity grids, notes the release, emphasising the need to “prepare, build resilience” into our communications systems.
Nine such extreme solar storms — known as Miyake Events — have now been identified as having occurred over the last 15,000 years. The most recent confirmed Miyake Events occurred in 993 AD and 774 AD. This newly-identified 14,300-year-old storm is, however, the largest.