Solar Cycle 25

The Sun emitted a significant solar flare peaking at 11:35 a.m. EDT on Oct. 28, 2021. NASA's Solar Dynamics Observatory, which watches the Sun constantly, captured an image of the event. Solar flares are powerful bursts of radiation. Harmful radiation from a flare cannot pass through Earth's atmosphere to physically affect humans on the ground, …

A mass of solar material that erupted from the Sun on Oct. 9, 2021, reached Earth on Oct. 12. The Earth-directed coronal mass ejection, or CME, elevated the Kp index, a measure of disturbance to Earth's magnetic field, to 6 (moderate level). Kp index levels range from 0 (quiet) to 9 (intense). The CME was …