Equinox Cracks?
The Sun and Earth are each surrounded by their own magnetic field. The Sun's magnetic field not only creates a safe 'bubble' around our solar system, but it also contributes to solar activity, such as solar flares and coronal mass ejections.
The Earth's magnetic field reacts to these solar storms, and to the flow of the solar wind, which results in coloured displays across our sky known as the Aurora Borealis, or the Northern Lights. Similar displays are seen around the south pole, known as the Aurora Australis or the Southern Lights.
Earth Magnetic Field Auroras - NASA
Auroras appear around the north and south poles of Earth as Earth's geomagnetic field traps particles from the solar wind and funnels them down into the atmosphere. (NASA)
READ MORE:Why are the Northern Lights so supercharged lately and how long will this last?
Due to Earth's tilt, our planet's magnetic field is nearly always out of alignment with the Sun's magnetic field. So, even under the absolute ideal conditions for a solar storm or the solar wind to result in auroras, that misalignment effectively reduces the overall intensity of any aurora display that does appear.
However, around the equinoxes, the magnetic fields of the Sun and Earth line up better than they do during the rest of the year.
Earth magnetic field tilt - NASA
The orientation of Earth's magnetic field at northern summer solstice (left), equinox (centre), and northern winter solstice (right). The Sun is located far off the left side of the field of view, and its magnetic field is oriented most in alignment with the centre panel. (NASA/Scott Sutherland)
This alignment causes the two magnetic fields to form strong connections with each other, which opens up 'cracks' in Earth's magnetic field. These cracks then allow more particles from the solar wind or from solar storms to stream down through that protective barrier and into upper atmosphere.
As a result of all this, auroras that occur around the spring and fall equinoxes can be some of the brightest and most colourful of the entire year!
Aurora-Borealis-March23-2023-TeamTanner
This colourful aurora display was captured by Tree and Dar Tanner from central Alberta, on March 23, 2023. (TeamTanner)
Writtenwith files from The Weather Network
Thumbnail image courtesy Matt Melnyk, who captured the aurora borealis north of Calgary, AB, over the weekend, and postedhis images to X. (Picture used with permission)
Watch Below: See Friday's amazing spring equinox aurora displays