Free Astronomy Magazine July-August 2024

JULY-AUGUST 2024 damage. A large financial, time, and manpower commitment would be required to preventively rebuild the electricity grids and communica- tions systems so that they could fully withstand a new Carrington Event, but governments around the world A very rare photographic documentation of the development of a white light solar flare, which appeared in a very active region on March 31, 2001. Despite an anomalous behavior in the radiation emission at high energies, there is no doubt that it was a phenomenon in some ways similar to that reported by Carrington, although much less energetic. [Antonio Finazzi, Chiuduno, Bergamo, Italy − adapted from l’Astronomia ] residues trapped in tree rings high- light Carrington-type events in 994 AD, 774 AD, and 660 BC, with the first and third significantly more powerful than the Carrington Event, which left no obvious radioisotope traces of that type. Searches even farther back in time, based on radioactive particles trapped in the ice of Greenland, report a possible very mighty geomagnetic storm dat- ing back 9,200 years. This apparent scarcity of events should not be misconstrued with inac- tivity, as randomness plays a non-negligible role; in the last week of July 2012, a mass of coronal plasma compa- rable to that of the Car- rington Event crossed the Earth’s orbit just 9 days ahead of when the Earth was to be at that very position. In order to have an overall picture of solar T he aurora on the horizon, photographed on May 10 th , near the St. Mary lighthouse in Whitley Bay, England. [Owen Humphreys/ Associated Press] have shown little-to-no interest in doing so. The unpredictability of CMEs is in- evitably reflected in estimates of their frequency, estimates which are characterized by a large margin of uncertainty. Studies of carbon-14