A Surge in Northern Lights: Exploring the Solar Maximum Phenomenon

A Surge in Northern Lights: Exploring the Solar Maximum Phenomenon

Recently, sky watchers in Edmonton and beyond have likely noticed an increase in the vibrant displays of the aurora borealis illuminating the night sky. This captivating natural spectacle can be attributed to the current phase of solar activity known as solar maximum.

During solar maximum, which aligns with the sun's approximately 11-year magnetic activity cycle, the sun exhibits heightened magnetic activity. Ian Mann, a space physicist from the University of Alberta’s Faculty of Science, emphasizes that this period is particularly advantageous for those who wish to witness the mesmerizing aurora displays. "If you want to watch beautiful shows of the dancing northern lights, solar max is an ideal time to do that," he notes.

The sun’s magnetic field undergoes a cyclical shift, flipping its poles and transitioning between periods of low activity, termed solar minimum, and high activity or solar maximum. During these solar maximum phases, phenomena known as “auroral ovals” expand closer to the equator, bringing auroral displays closer to populated areas. Mann describes this phenomenon as a “double whammy” for aurora enthusiasts—more energy translates to more powerful displays that are also more accessible to viewers.

This period of heightened solar activity also opens new avenues for scientific exploration, as Abigail Azari, an assistant professor in physics and electrical and computer engineering at the University of Alberta, notes. She highlights that the factors affecting Earth during solar maximum could similarly impact other planets, prompting opportunities for comparative studies across the solar system.

Before the dazzling colors of the aurora can manifest in the night sky, explosive activity must occur on the sun’s surface. Richard Sydora, a professor in the Faculty of Science, explains that the sun's surface is teeming with bundles of strong magnetic fields that form sunspots. When these magnetic loops explode, they release coronal mass ejections—massive bursts of charged particles propelled into space.

Though Earth’s magnetic field generally deflects these charged particles, during intense solar activity, a portion penetrates this shield. The interaction of solar wind—a flow of charged particles—colliding with Earth's magnetic field transfers energy into the near-Earth space, creating the conditions necessary for the auroras.

As the charged particles, primarily electrons, cascade down toward Earth, they collide with gaseous atoms and molecules in the upper atmosphere, typically between 100 to 250 kilometers above sea level. These collisions prompt the particles to emit light as they revert to lower-energy states, resulting in the stunning visual effects observed during auroras.

The colors displayed during auroras are determined by the types of gases involved in these collisions. The dominant green hue, often associated with auroras, originates from interactions with oxygen atoms, while higher-energy collisions may yield red shades. Nitrogen particles contribute to the blue and purple tones frequently noticed in auroral displays.

To optimize your aurora viewing experience during this solar maximum, interested observers are encouraged to sign up for the University of Alberta's Aurora Watch email alert service. This service provides updates on geomagnetic activity levels, detail on the probability of witnessing an aurora, and ideal viewing times. Although the auroras can sometimes be seen from urban backyards, finding a darker area free from light pollution enhances the viewing experience, with midnight frequently cited as a prime time for visibility.

For those hoping to capture the full spectrum of colors during an aurora display, it is recommended to use cameras, even those on smartphones, as they possess a greater sensitivity to different wavelengths of light compared to the human eye. As Mann advises, patience is key: there may be long stretches of inactivity, but the reward of a sudden burst of vibrant lights can be breathtaking.

Stay tuned and keep your eyes on the sky as these spectacular natural displays continue to grace the night with their beauty during the current solar maximum.