There is an excellent reason for the observed increase in the frequency and northward spread of the southern lights. We are heading towards the solar maximum. Solar maximum is the apex of the 11-year solar cycle when sunspots are most abundant and auroral activity flourishes. The current cycle, which began in December 2019, is expected to peak in 2025 or 2026. This cycle is much more active than predicted, which causes aurora chasers like me to get very excited. The best may be yet to come!
A superb example of what we might expect to see in the coming months was the April 24 aurora. An explosion had occurred on the Sun a few days beforehand, directing vast quantities of solar ejecta on a collision course with Earth. Just before dawn, when that material reached our planet's magnetic field, the southern sky exploded into life in a powerful solar storm. Some spectacular pictures were obtained in the run-up to dawn when the brightening daytime sky hid the aurora from view. But this storm had legs, and as dusk turned to night, crowds of aurora chasers could experience the fantastic show from locations across the south island.
With much of the action occurring in the southern sky, from my favourite observing perch in Hoopers Inlet, something unique caught my eye just after 9.30 pm. A bright pinky-white beam of light was passing almost overhead. I immediately pointed my camera to record what I knew to be a scarce non-auroral phenomenon usually only seen during the most potent auroral storms. Steve was paying a visit!
Steve is a typically unimaginative scientific acronym. It stands for Strong Thermal Emission Velocity Enhancement. Steve is a fast moving atmospheric river of high-temperature plasma whose formation and mechanism are not understood by researchers. There's a lesson here for all aurora chasers. When there’s a glow in the south, remember to check the rest of the sky. You never know if Steve will be paying a visit.
