NASA has warned of strong solar flares that have the potential to interrupt communications in space and down here on Earth.

The aerospace agency on Thursday posted news of a flare that peaked at 5:34 p.m. EST on Feb. 22, 2024 (10:34PM UTC) that it’s rated an X6.3 event.

Solar flares are rated in five categories: A, B, C, M, and X. A C-class flare is ten times more powerful than a B-class event, and an M-class event is ten times more powerful than a C-class event. Flares are also scored with a numerical value to indicate the magnitude of the event.

X-class flares are therefore significant. And this one is a very big one: a list of historical solar flares at Space Weather Live suggests this event was the 27th-most-powerful flare recorded and the biggest since 2017. The list’s biggest event was rated an X40.

The X6.3 flare followed an X1.8 flare on Wednesday and an X1.7-rated event earlier on Thursday. Here’s NASA’s snap of the X6.3 flare.

The US National Oceanic and Atmospheric Administration warned that the X6.3 event could mean “temporary degradation or complete loss of signal” for operators of high frequency radios - at least on the sunlit side of the planet at the time of the flare - and added that the event “poses no significant threat to the general public”.

But the Administration earlier advised that all flares have the potential to mess with radar and GPS.

Solar flares are also no joke for astronauts, as they produce dangerous radiation. The seven crew aboard the ISS and the three aboard China’s Tiangong space station therefore have cause to be nervous if the current round of flares escalates. The ISS crew have no duties over the weekend.

While notable, the flares were not responsible for the cellular network outages experienced across the USA today.

These flares occurred during Sun Cycle 25, which started in 2019 and is predicted to run until around 2030, with its peak in 2025. This X6.3 flare is the biggest of this cycle, but probably won’t keep that title. ®

https://www.theregister.com//2024/02/23/solar_flare_warning/