DISCUSSION: Earlier this week, electromagnetic radiation from the Sun collided with the Earth’s magnetic field to put on quite the show for many across Northern Europe. People in Estonia and Denmark captured some breathtaking photos, and shared them onto Facebook for all to see and enjoy. Auroras occur when a sunspot on the surface of the Sun emits charged particles out into space via a solar flare. These charged particles get carried towards Earth by the solar wind where they then collided with the Earth’s magnetic field, specifically at the North and South poles where the magnetic field is weaker. At the poles, photons and electrons from the sun collide with gas particles in the Earth’s atmosphere to give us what we know as auroras. Oxygen lower in the atmosphere gives us the typical green auroras as seen in the majority of pictures, while oxygen higher up in the atmosphere gives us bright red auroras. Nitrogen on the other hand, gives us a very vivid blue and violet light show. A variety of colors were shown in various photos seen on Facebook across Northern Europe.
As forecasted, a mild G1-class geometric storm reached the Earth’s surface late in the day on August 2nd, and lasted well into the early morning hours on August 3rd. NOAA breaks down the scale into 5 distinct levels to describe the intensity of the solar flare, with G1 being the mildest up to G5 becoming extreme. Auroras are quite common near the North and South poles throughout the entire year. It’s been a while since we have seen a G5 geometric storm, however a G4-class storm did occur in March of last year and threatened to damage satellites and transformers, but that did not occur. This most recent geometric storm comes after the Sun was in a relatively peaceful “sunspot free” period. NOAA forecasters say that there is no need to panic as this is quite normal in the Sun’s 11-year natural variability cycle. Do you have any pictures of the recent auroras? Please feel free to share in the comments below! To learn more about other high-impact weather events from across Europe, be sure to click here!
@Meteorologist Jake Keiser