X-class solar flare was erupted from sunspot AR3354 as a result of sunspot explosion on July 2. This caused radio blackout over parts of U.S. and the Pacific Ocean.
The newly membered sunspot region, AR3354, is seven times the width of the earth. The huge sunspot was visible to naked eye (could watch safely using solar glasses) from June 26 to July 2, 2023. By observing the rapid growth rate of the sunspot, Keith Strong, solar physicist had predicted flares from it.
Th U.S. National Oceanic and Atmospheric Administration (NOAA) had predicted a 40% chance for the occurrence of M-class solar flare and a 10% chance for the occurrence of X-class solar flare.
NASA’s Solar Dynamic Observatory (SDO) saw the flare as bright ultraviolet flash and classified it as an X-flare, belonging to X1-class. The flare resulted in a deep short wave radio blackout for 30 minutes over the western parts of the U.S. and the Pacific Ocean. The radio blackout was classified as an R3. Radio blackout occurred due to ionization of top of earth’s atmosphere by ultraviolet radiation from the flare.
Keith Strong had shared the footage of the X1.07 flare on twitter. It is the 18th X flare in the current solar cycle (solar cycle 25). June 2023 had marked the highest monthly average for number of sunspots in 21 years.
The flare was helped along by a plume of plasma, causing magnetized material to land on the sunspot AR3354.
X-class Solar Flare
Flares are the result of reconnection of powerful magnetic fields in and around the sun.

X-flare is the strongest type of solar flare that exists. A powerful X-class flare can cause long lasting radiation storms that can harm satellites and give small doses of radiation to airline passengers flying near the poles. They have the potential to create global transmission problems and world-wide blackouts.
Classification of Flares
The solar flares are classified into B, C, M, and X, where each letter indicates a ten-fold increase in energy output. Within each letter, there is a finer scale from 1 to 9.
X-flares can go higher than 9. A powerful solar flare recorded in 2003 was estimated to be about X45.
The recent X-flare was enough to trigger a coronal mass ejection (CME). But the sun observatories have not yet seen a significant plasma ejection associated with this flare. (Coronal mass ejections are large expulsions of plasma and magnetic field from sun’s corona).