March and April were surprisingly active months for the Sun. In fact, it was just the sort of activity we like. Had the intensity of the Sun's geomagnetic outbursts been much greater, we might have faced damage to satellites or power lines. Instead, all we got was some stunningly beautiful auroras.
After a substantial but greatly overhyped event in March, mid-April saw three “coronal holes” open up on the Sun's surface, causing a stronger-than-usual solar wind to rush towards Earth. A few days later, our neighborhood star produced a large geomagnetic storm that lit up our skies.
When the storm was first announced, the National Oceanic and Atmospheric Administration described it as a G1, the lowest category of storm. However, over the next few days, it was upgraded until it became the biggest G2 for quite a while on April 20th. Although auroras occur in the absence of storms, they retreat closer to the magnetic poles, where few people get to witness them. It's events like this one that push them out where more people can enjoy them.
Many people close enough to one of the Earth's magnetic poles had their views blocked by clouds, but in parts of Tasmania and southeastern Australia, the sky was stunningly clear.
Meanwhile, on the other side of the world, auroras so bright they could be seen in daylight were reported in Montana.
Aurora photography has really taken off in recent years thanks to the boom in digital cameras. This hasn't just produced a stunning collection of photographs such as these (and earlier examples), it's also led to the discovery, first made by amateurs, of an entirely new type of aurora, which somehow got the name Steve.
The Sun goes through an 11-year activity cycle, but the most recent peak, from 2012-2014, was much less intense than any previous cycle since 1830. We're now getting close to the solar minimum, so storms like this are unusual.
Eighteen years ago, when magnetic storms like this were relatively frequent, most people lacked the technology to record them. Today, digital cameras, editing programs, and the skills to utilize both are now widespread. Unfortunately, we're now in a solar minimum, so there are fewer spectacular auroras to record. That will change in another 2-3 years, however, when the cycle should turn and auroral activity should become more common. And when that happens, just think of the feast for our eyes we can expect
Until then, cherish images like this, taken from Stawell, Victoria, a place usually too far from the magnetic pole to experience any auroras at all.