The sun has had an active Fourth of July week, setting off a number of fireworks of its own. Sunspot AR1515 let lose with an X class solar flare on Friday, after a week of powerful ejections. An M class flare, earlier in the week caused a minor radio blackout. This one does not appear to be aimed directly at Earth but may cause further radio disruption.
The most powerful solar flare of the summer erupted from the sun on Friday, marking the latest in a string of strong storms this week from our home star.
The sun storm occurred just after 7 p.m. ET and registered as a class X1.1 solar flare — one of the strongest types of solar flares possible, according to the U.S. Space Weather Prediction Center, run by NOAA and the National Weather Service.
The huge solar flare erupted from the giant sunspot AR1515, which has already fired off several other powerful storms this week. Space weather scientists were closely watching the sunspot for possible X-class flares.
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In a new alert announcing the X-class solar flare, SWPC officials said the sun storm could a "wide-area blackout" in the high-frequency radio communications.
It looks like this one should miss us completely but it's a powerful reminder of the damage one of these things can do if it's aimed straight at the planet. From SpaceWeather:
The explosion hurled a CME into space. According to this movie from the Solar and Heliospheric Observatory, the cloud appears to be heading south and away from Earth. Update: Analysts at the Goddard Space Weather Lab say the CME will miss eveything. Their forecast track shows the cloud not hitting any spacecraft or planets.
The storm on sunspot AR1515 is ongoing and more CMEs are likely.
If you wish to understand why NASA is watching the sun so closely these days, it's because of a genuine threat to a world as technologically advanced -- and technologically dependent -- as ours has become. A Carrington Event of the magnitude of the one for which they are named could hurl us back to an early 1800s lifestyle... or worse.
Solar activity peaks every 11 years sending waves of charged particles careening toward the earth at speeds over 1,000 miles an hour. Much of this energy is absorbed by the upper atmosphere, but some of it gets through and hits the surface of the earth -- fortunately at levels too low to cause direct damage to humans. It can, however, interfere with the high power transmission lines which crisscross the U.S. When these lines get overloaded, they can knock out and sometimes destroy the transformers whose task it is to step down the voltage which passes through them. This is what led to the blackout in Quebec.
But scientists know that vastly larger and more destructive solar storms than this are not just possible, but inevitable. The last recorded Solar Superstorm called the "Carrington Event" occurred over a period of nine days in 1859. It is is believed to have been caused by an explosion on the sun equivalent in force to a billion hydrogen bombs. Auroras were seen as far south as the Caribbean, and telegraph networks failed across the Northern Hemisphere, in some cases even catching fire.
Nobody knows when another storm of this size will envelop our planet, but a recent estimate published in the International Journal of Research and Applications says that there is a one in eight chance of this happening within the next decade. If it does, electrical grids throughout the world will not just fail, but be destroyed. NASA warns that such an event would cause "an avalanche of blackouts carried across continents [that] ... could last for weeks to months."
Some experts worry that it could actually take years to rebuild our grids and networks. So, yeah, the sun merits watching.