Massive X-Class Solar Flare Erupts, Causing Widespread Pacific Radio Blackouts

A powerful X1.9-class solar flare blasted out of the sun's active region 4114 on June 19, peaking at 9:50 p.m. EDT (0150 GMT, June 20), and led to a shortwave radio blackout over the Pacific Ocean and, in large part, for Hawaii. Although the flare was accompanied by a sizable eruption of X-ray and ultraviolet light, it did not appear to be associated with a very powerful coronal mass ejection (CME), so there will be no auroras for hopeful skywatchers at this time. The energetic flare, however, destabilised a substantial magnetic filament in the southern hemisphere of the sun, hinting at more activity to come.

X1.9 Solar Flare From Sunspot 4114 Disrupts Radio Signals, Sparks Fears of Future Geomagnetic Storms

As per Space Weather Live and spaceweather.com reports, the electromagnetic radiation from the flare reached Earth within minutes, ionizing the upper atmosphere and disrupting shortwave radio communication below 25 MHz. In the Pacific region, ham radio operators reported an abrupt loss of signals following the peak of the flare. That happens due to a powerful solar disturbance that collides with the Earth's ionosphere, increasing electron density and weakening the ability to absorb high-frequency signals. The outcome is signal attenuation or loss, as normally occurs during periods of intense solar activity.

Solar flares are ranked in strength, and X-class flares are the most intense ones. The flares from sunspot 4114 — rated at X1.9 — are one of the strongest in the current solar cycle. It follows an earlier eruption from the same region just days ago, rated at X1.2. The region has now drawn close monitoring due to its continued magnetic complexity and explosive potential.

Although no CME accompanied the latest flare, experts suggest future eruptions from region 4114 could be more geoeffective. If a CME is launched in subsequent flares, geomagnetic storms and auroral activity may follow.

Space weather forecasts and aurora updates are available on NOAA's 3-day geomagnetic outlook and dedicated solar activity blogs.