By PAUL HETZLER
“Solar Max.” If there isn’t one already, there ought to be a band by that name. Or maybe a renewable-energy superhero.
Solar max, or maximum, refers to the period of high sunspot activity in the sun’s approximately 11-year solar cycle, and it's usually a time when we see the northern lights, or aurora borealis, more often.
Although it hasn’t turned out to be the most memorable of maxes, we’re now in the midst of a solar max, which could yet provide North Country residents a good light show.
Energy that constantly emanates from the sun in the form electrons, x-rays, gamma rays, UV light, visible light and other forms of radiation is referred to as solar wind. While there’s always a breeze, sometimes the wind kicks up, and every so often a storm develops. No one knows what causes solar storms, but astronomers can “spot” when one is brewing.
All stars eventually develop spots. Some pout and slink off for cosmetic surgery. Other stars, our sun for example, produce areas of intense magnetic activity—sunspots—on a regular basis. It's not certain if they actually cause other powerful phenomena, but sunspots almost always appear just prior to solar flares and coronal mass ejections (CMEs). Flares and CMEs are “wind gusts” of solar radiation which emerge from areas near sunspots. The radiation they thrust into space is also known as plasma.
If astronomers observe unusually large sunspots, they keep an eye out for subsequent activity. When a strong CME erupts, it sends high-energy plasma in our direction at speeds of up to 1,800 miles per second. In roughly 24 hours this blast reaches Earth and reacts with its outer atmosphere to produce a geomagnetic storm.
When our favorite sun hurls lethal radiation towards us, we can thank our lucky stars we have a molten core with a high percentage of iron. Or at least that our planet does. This core induces a magnetic field around Earth, thus deflecting radiation and saving us from becoming the toast of our town. As the stream of radiation bends around Earth like water around a rock, some charged particles are “herded” toward the north and south poles, resulting in the aurora borealis and aurora australis, respectively.
Geomagnetic storms don't just put on psychedelic light shows. They're capable of real mischief, and can harm or even disable satellites. In most cases satellites can be moved out of harm's way, or at least turned to shield their solar panels. Storms can also damage electric devices and infrastructure. In March 1989, a geomagnetic storm shut down Hydro-Quebec's state-of-the-art power grid within seconds of hitting Earth, creating a record outage that left six million customers without power. Radio and cell phone transmission was also interrupted, and the aurora borealis was seen as far south as Texas.
The most famous solar event occurred in September 1859 following two massive, consecutive solar flares. Telegraph systems failed. The aurora borealis was seen in the tropics, and in the northeast was bright enough to read by. In 2013, Lloyd's of London calculated that such an event today would cause 2.6 trillion dollars in damage. A Metatech study concluded the world's electric grid could be out for several months, with losses even higher than that. I wonder if that includes deleted Bitcoin currency.
For all the time and effort that goes into studying solar phenomena, much is yet unknown. One unexplained fact is that auroras are more active around the time of the equinoxes. Since we're in solar max and March 21 is fast approaching, it's worth checking the northern sky before going to bed. If you don't mind spoiler alerts you can go to noaa.gov and check the space weather forecast, which will indicate if an aurora is expected that night, and presumably whether you'll need your space heater.
Paul Hetzler is a forester and Cornell Cooperative Extension of St. Lawrence County horticulture and natural resources educator.