The Aurora Borealis? At this time of year? At this time of day? In this part of the country? Localized entirely within your kitchen?
You might have noticed an increase in the number of sightings of auroras this year in areas they usually shouldn’t be, like the Midwest. Beautiful, sure, but maybe a little confusing. The northern lights are known to be seen in arctic regions, but lately the lights have been moving around, all thanks to the sun’s recent behavior.
Our sun is currently approaching its solar maximum, a period where electro-magnetic activity is at its peak. This is expected to happen within the next year, during our current solar cycle 25. Solar cycles are determined by the amplitude, or maximum number, of sunspots over time. As we approach solar maximum, the number of sunspots will continue to increase, creating more chances for Coronal Mass Ejections, or CMEs. And solar flares have a higher chance to be ejected from the sun - potentially towards our planet.
These solar events pose risks for satellite communications, radio, and our power infrastructure, but they can also make some stunning visuals in the night-time sky, depending on the severity of the storm. Storms that are particularly strong can cause interferences in Earth’s magnetic field that make the auroras to be visible in lower latitudes than normal - like the Midwest.
How do scientists study solar activity?
Scientists study solar activity by observing the number of sunspots. Sunspots are concentrations on the sun that pop up where the magnetic field is stronger than other areas of the sun - and about 2,500 times stronger than Earth’s magnetic field.
Sunspots are formed where opposing magnetic fields become entangled. The battle between magnetic forces happening in these areas can cause solar flares and CMEs to be launched into space. Solar flares are characterized as a bright flash of electromagnetic radiation that travels at the speed of light. Solar flares have the potential to wreak havoc on high-frequency radio signals in the ionosphere. Such incidences can cause a degradation of signal quality due to the collisions between electrons in the atmosphere.
CMEs, on the other hand, are ejections of plasma and magnetically-charged particles that can take a bit longer to arrive. CMEs are often associated with an initial solar flare. It is a combination of these solar projectiles that can cause disruptions of Earth’s magnetic field, creating beautiful light shows. We are currently about half-way through solar cycle 25, with scientists estimating the peak to occur sometime in 2025
Space Weather Forecasts
This past May, a G5 storm composed of several M-class solar flares and multiple CMEs hit Earth, causing auroras to be visible at lower latitudes, including right here in AMOS' backyard, Bloomington!
You can keep updated about space weather and find out if you can see an aurora in your neighborhood on the Space Weather Prediction Center’s website.
Space weather can be beautiful, but next week on the blog, we’ll take a look at when it gets dangerous.
Learn more:
- Will the sun’s magnetic field flip this year? (and how the sun actually works)
