Skygazers in North America are in for a treat this weekend, as the National Oceanic and Atmospheric Administration (NOAA) predicts increased visibility of the northern lights. This follows the sun’s release of a potent “cannibal” solar storm earlier this week.
Recent solar storms and their impact
Residents of Canada, Alaska, Minnesota, Wisconsin, and the Dakotas were treated to a stunning display of northern lights after two powerful blasts of solar radiation merged on their journey to Earth. These combined forces formed a massive “cannibal” solar storm, which struck our planet on Tuesday and Wednesday. For those who missed this celestial show, there may be another opportunity to witness the dazzling lights. NOAA forecasts another solar blast likely to impact Earth on Saturday.
Understanding solar maximum and coronal mass ejections (CMEs)
At Solar Maximum, the sun exhibits a series of complex sunspots, leading to frequent eruptions of material from its surface known as Coronal Mass Ejections (CMEs). These CMEs occur when the sun’s magnetic field suddenly snaps and realigns, sending energetic charged particles into space. When these particles reach Earth, they interact with our planet’s magnetic field, resulting in mesmerizing auroras.
Why auroras are more visible near the poles
Auroras are more prominent near the north and south poles due to the stronger magnetic fields in these regions. Known as aurora australis in the southern hemisphere and aurora borealis in the northern hemisphere, these light displays can stretch closer to the equator during more intense solar storms. The variety of colors in an aurora display is due to different molecules in the atmosphere being charged by the geomagnetic storm. For example, oxygen in the upper atmosphere emits a fluorescent green and yellow hue when it interacts with a solar storm, while nitrogen produces blue, red, or sometimes pink colors. Neon, on the other hand, glows orange.
Geomagnetic storms are classified by the letter G and rated on a scale from 1 to 5, with 1 indicating a minor event and 5 signifying an extreme one. NOAA has issued a G2 storm alert for August 3 and 4. It is worth noting that G2 and G3 storms can interfere with power grids and cause voltage fluctuations. Skygazers are advised to stay alert and keep their eyes on the skies for a chance to witness this extraordinary natural phenomenon.