SOLAR‑TERRESTRIAL DATA
SOLAR‑TERRESTRIAL DATA
Key for These Charts
SFI – Solar Flux Index
70 – Not Good • 80 – Good • 90 – Better • 100+ – Best
A‑Index – Daily Magnetic Activity
0–7 Quiet • 8–15 Unsettled • 16–29 Active • 30–49 Minor Storm •
50–99 Major Storm • 100–400 Severe Storm
K‑Index – Updated Every 3 Hours
0 Inactive • 1 Very Quiet • 2 Quiet • 3 Unsettled • 4 Active •
5 Minor Storm • 6 Major Storm • 7 Severe • 8 Very Severe • 9 Extremely Severe
