Solar Maximum
Solar maximum is the phase of the roughly 11-year solar cycle when the Sun is most active. Sunspot number is high, and solar flares and coronal mass ejections (CMEs) are more frequent. As a result, geomagnetic storms and aurora are more likely. The current cycle (Cycle 25) is expected to peak around 2024–2026.
Solar Minimum
Solar minimum is the phase when activity is lowest: few or no sunspots, fewer flares and CMEs. Geomagnetic activity and aurora are less common, though high-speed solar wind from coronal holes can still cause occasional storms. The cycle then rises again toward the next maximum.
Sources and further reading
- NOAA – Solar cycle – Sunspots and cycle phases
- NASA – Solar cycle – Space weather and the cycle