Northern Lights

What is a Northern Light? Have you ever had the opportunity to witness a Northern Light? This natural phenomenon is a breathtaking spectacle that illuminates the night sky with vivid colors. Although it is a rare event in regions like Paris, it is far more common in northern countries such as Norway.

Polar Auroras: Northern and Southern Lights It is important to clarify that the term "Northern Light" is specific to the Northern Hemisphere. The phenomenon also occurs in the Southern Hemisphere, where it is called the "Southern Light." The term "Polar Auroras" thus encompasses both phenomena.

Where and When to Observe Them? To maximize your chances of witnessing a Northern Light, the optimal location is above the Arctic Circle, in an area called the Auroral Oval. This zone extends between 65 and 75 degrees of northern latitude and covers regions such as northern Scandinavia, northern Russia, Iceland, Greenland, the Canadian Arctic, and Alaska.

How Do They Form? Northern Lights result from the interaction between charged particles emitted by the Sun and Earth's magnetic field. The Sun emits a continuous flow of particles, primarily protons and electrons, at a speed of approximately 1.3 million kilometers per hour. These particles form what is known as the "solar wind." Fortunately, Earth's magnetic field acts as a shield, deflecting the majority of these particles and directing them towards the poles. When these particles collide with atoms in Earth's atmosphere, they create the magnificent lights we call Northern Lights.

Are They Dangerous? There is no danger associated with observing Northern Lights. They occur at very high altitudes, between 80 and 300 kilometers above Earth's surface, and are therefore entirely harmless to humans.

The Fascinating Colors of Northern Lights Northern Lights captivate with their variety of colors: green, red, blue, purple—there is something for everyone. These colors vary depending on the atoms ionized by the solar particles and their altitude in the atmosphere. For example, when low-altitude oxygen atoms are ionized, they emit green radiation. This green is particularly perceptible because it is close to us, and our eyes are especially sensitive to it. At altitudes above 200 kilometers, these same atoms emit a deep red, more difficult to perceive with the naked eye. Sometimes, the horizon fills with a spectrum of purple, blue, pink, or white, emitted by nitrogen atoms located closer to us.

When and Where to Observe This Phenomenon? To observe a Northern Light, one must wait for nighttime, as the light emitted by the atoms in the atmosphere is not powerful enough to be visible during the day. The best period to observe this phenomenon in the Northern Hemisphere is between November and March when the nights are very dark and very long. The spectacle is generally most intense between 8 p.m. and 1 a.m. It is also advisable to choose periods of new moon or dark moon to maximize darkness and make the auroras more visible.

The Ideal Location The ideal location to observe this spectacle would be in northern Norway, on the Svalbard archipelago. But beware, temperatures can drop to -30 degrees Celsius, so do not forget your mittens and fleece!

Northern Lights as Seen from Space Thomas Pesquet, a well-known French astronaut, had the unique opportunity to photograph the Northern Lights from the International Space Station. The images clearly show green auroral arcs undulating above Earth.

Is it Possible to See Northern Lights in Paris? Although extremely rare, it is theoretically possible to see a Northern Light in Paris. On the night of January 25, 1938, a Northern Light illuminated the Parisian sky. This exceptional phenomenon was due to a particularly violent solar storm that distorted Earth's magnetic field lines, allowing solar particles to penetrate as far as the tropics.

The Dangers of Solar Storms It is important to note that solar storms can also create magnetic storms capable of disrupting electrical grids and the internet across a large part of the globe.

The Next Peak of Activity The Sun enters a phase of maximum activity approximately every eleven years. The next peak of activity is expected in 2025, and Northern Lights are anticipated to be particularly intense during this period.