Solar Eruption Triggers Geomagnetic Storm Alert

On September 28, a solar filament erupted, releasing a massive amount of plasma towards Earth. NOAA (National Oceanic and Atmospheric Administration of the United States) classified the ensuing geomagnetic storm as G1, the lowest level on the effects scale.

What Caused the Storm

The rupture of a filament – a dense “ribbon” of plasma held by magnetic forces – triggered a coronal mass ejection (CME). This CME, traveling through space, will hit Earth via a “graze impact,” according to a NOAA space weather meteorologist.

When Will It Reach Earth

The effects of the solar activity are expected to reach Earth's magnetic field on Friday, October 2, and again on Sunday, October 4. For Saturday, October 3, the forecast indicates calm conditions, with indices below storm level.

Predicted Impacts

A G1 storm does not cause harm to the population or significant disruptions to daily routines. Mobile phone networks, broadband internet, and terrestrial TV transmissions will not experience interference or signal outages. Small variations in GPS signals and occasional fluctuations in high-frequency (HF) radio communications may occur. Insignificant voltage fluctuations in power grids located at very high latitudes are also possible.

What to Expect for Auroras

The conditions created by the coronal mass ejection and the heart-shaped coronal hole at the center of the solar disk are favorable for observing auroras in the coming nights, especially at high latitudes.

Monitoring and Forecasts

During the period from September 30 to October 2, NOAA calculates a daily 10% probability for radio blackouts between R1 and R2 levels and a 1% probability for solar radiation storms of S1 level or higher. Earth's geomagnetic activity remains very quiet, with the Kp index ranging from 0 to 1.

With information from CNN Brasil, Diário do Comércio, Exame.