Real-Time GOES-Primary Satellite Soft X-Ray Irradiance (0.1–0.8 nm) & Solar Flare Activity
Solar flares are categorized by their peak flux in the 1–8 Å (0.1–0.8 nm) soft X-ray band measured by the GOES satellites:
| Class | Peak Flux (Watts/m²) | Impact |
|---|---|---|
| A / B | < 10⁻⁶ | Quiet Sun background; negligible impact. |
| C | 10⁻⁶ to 10⁻⁵ | Minor flare events; usually no radio disruption. |
| M | 10⁻⁵ to 10⁻⁴ | Medium flares; triggers R1–R2 HF radio blackouts. |
| X | > 10⁻⁴ | Major flares; causes severe R3–R5 planetary blackouts. |
During the vernal and autumnal equinoxes (March and September), geostationary GOES satellites pass directly through the Earth's shadow each night (around 08:30–09:45 UTC for GOES-West).
During this 45–70 minute eclipse totality, the Earth blocks the Sun from the X-ray sensor, causing artificial zero-drops or blackouts. When enabled, the monitor automatically detects the shadow window on the fly and extrapolates the true solar flux background linearly between ingress and egress.