With a burst of solar activity, the northern Lights were visible as far away as Oklahoma and North Carolina on Thursday night and early Friday morning. The aurora can also be seen in the UK and northern Europe.
The Northern Lights were very active in many parts of the United States and Canada on the night of March 23.
The sun has been in turmoil recently, with frequent solar flares, tornadoes more than 14 times the size of Earth, and eruptions that have thrown massive clouds of stellar particles across the solar system.
Thursday night and early Friday morning, these ingredients combined to explode the northern lights over Canada and the northern United States, stunning stargazers and even impressing photographers who often capture awe-inspiring images of the aurora.
On Thursday night, in cloudless weather, photographers captured stunning images of the aurora from coast to coast. Unfortunately, cloudy conditions, heavy rain and severe thunderstorms obscured the aurora from parts of the mid-Atlantic to the southern Plains.
So, do you know how the Northern lights are created?
How the Northern Lights are formed
At the South Pole, they’re called the aurora australis, and at the North Pole, they’re called the auroraalis. Earth’s auroras are created when a stream of high-energy charged particles (the solar wind) from the Earth’s magnetosphere or the sun excites (or ionizes) molecules or atoms in the upper atmosphere.
Auroras are often seen at latitudes close to the geomagnetic poles and are generally band-like, arc-like, curtain-like or radial, sometimes stable and sometimes changing in a continuous pattern. Auroras are created by three conditions: the atmosphere, a magnetic field and high-energy charged particles.
Modern physics describes in detail how the aurora borealis is created. The aurora borealis on Earth is a luminous phenomenon caused by charged energetic particles from the magnetosphere and the solar wind being guided into the Earth’s atmosphere by the geomagnetic field and colliding with atoms in the upper atmosphere (thermosphere). Auroras are not only found on Earth, but also on some of the other planets in our solar system that have magnetic fields.
According to studies on the distribution of auroras, the shape of the auroral zone is not circular, centred on the geomagnetic pole, but oval. The spectral lines of the aurora range from about 3100 to 6700 Å. The most important spectral line is the green line of the oxygen atom at 5577 Å, called the auroral green line.
Most auroras occur 90-130 km above the Earth. in 1959, one aurora borealis was measured to be 160 km high and over 4800 km wide. However, some auroras are much higher, reaching heights of 560-1000 km or more.
When is the best time of year to see the Northern Lights?
To see the aurora borealis, the northern lights can be seen under dark skies from late August to mid-April, but preferably under clear, cloudless skies Although they occur throughout the year, they are weaker than sunlight, making them impossible to see from May through July and much of August.
Spring and fall usually have more stable weather conditions and mild temperatures, plus more auroral activity near the vernal equinox.
From November to February, when the skies are darkest and the nights are longer, you can enjoy the sky watching.
The strongest lights tend to appear between 9 p.m. and 2 a.m., though the best views usually occur between 11 p.m. and midnight.
Between 4 a.m. and 5 p.m., there’s usually too much daylight to see the aurora – the exceptions are the darkest months of the year and high latitudes like Svalbard, where it’s dark 24 hours a day from mid-November to late January.
Why is auroral activity stronger near the equinoxes?
Because of the axial tilt, the Angle of our magnetic field relative to that of the solar wind changes as the Earth moves around the sun. At its best, during the equinoxes, “magnetic cracks” open, allowing solar particles to trigger auroral storm cycles, which in turn create a higher probability of northern lights.