Sun · Space Weather
Solar Flare Tracker and Current Solar Activity
See the current X-ray flare class, 6-hour peak, and the most recent flare on the full Sun dashboard:
Open the live solar flare chart →What this means
The GOES X-ray Sensor (XRS) measures soft X-rays coming from the Sun. The brightness of that signal is binned into letter classes, each 10× stronger than the last:
- A & B — quiet background, no Earth impact.
- C — minor flare, usually no noticeable effect.
- M — moderate flare, can cause brief radio blackouts on Earth's dayside.
- X — major flare, strong blackouts, possible coronal mass ejection (CME).
How to read this data
The X-ray flux line on the chart climbs and dips with solar activity. Each horizontal band marks a class threshold. A flare is counted when the flux crosses one of those thresholds and then peaks before fading.
The "current" reading is the latest 1-minute average. The "6h peak" is the highest level reached in the last six hours. The "last flare" is the most recent event NOAA has officially logged.
Why it matters
Large flares — especially M- and X-class — can disrupt high-frequency radio, GPS accuracy, and satellite operations. When a flare is paired with a CME aimed at Earth, it can trigger geomagnetic storms and visible auroras a day or two later.
Tracking flare activity helps amateur radio operators, pilots, satellite operators, aurora chasers, and students of space weather understand the current state of the Sun.
Live data updates approximately every minute from NOAA SWPC.
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Created by Nicholas Tyo