Sunspot explodes, produces strongest solar flare in 7 years causing radio blackout

Sunspot AR3842 exploded on October 3, producing the strongest solar flare in seven years, SpaceWeather reported. Radiation from the flare ionised the top of Earth's atmosphere and caused a deep shortwave blackout over Africa and the South Atlantic, the report said. Ham radio operators may have noticed loss of signal at frequencies below 30 MHz for a while, it added.