Space Weather

Solar Flares

Solar flares — sudden bursts of radiation from the Sun — and the A–X classification that ranks them. Recent flare activity is prepared for NASA DONKI and NOAA SWPC; none is fabricated.

Night SkyReference data

What a solar flare is

A solar flare is a sudden, intense burst of electromagnetic radiation from the Sun's atmosphere, often near sunspots. The strongest can disturb radio communications and, with an accompanying coronal mass ejection, trigger geomagnetic storms and aurorae at Earth.

The flare classification (A–X)

Class A: Background level; negligible effects.
Class B: Minor; no noticeable effects.
Class C: Small flares with few noticeable consequences.
Class M: Medium flares; can cause brief radio blackouts and minor radiation storms.
Class X: The most intense flares; can trigger planet-wide radio blackouts and strong radiation storms.

← Space weather · Geomagnetic storms →

Sources & references

Facts on this topic will be cited from these primary and reference sources.

NASA DONKINASA Community Coordinated Modeling Center
The Space Weather Database Of Notifications, Knowledge, Information: solar flares, CMEs, and geomagnetic storms.
NOAA SWPCNOAA Space Weather Prediction Center
Space-weather forecasts and alerts: aurora (OVATION), the Kp index, and the G1–G5 geomagnetic storm scale.

Loading…