This phenomenon usually visible only once a decade has just taken place twice in two months. After already a celestial spectacle “exceptional” in February, the aurora borealis were again visible on the night of Sunday April 23 to Monday April 24 in France. Neon pink and green colors, visible to the naked eye, lit up the skies across the country, the phenomenon was visible from north to south. “I was happy to see the images this morning but a little disappointed to have missed them. The night owls had a great show”confess to Freed the researcher and president of the French Astronomical Society, Eric Lagadec.
In question: a strong geomagnetic storm, writes the meteorologist Guillaume Séchet on Twitter. When the sun experiences strong eruptions, it ejects hot gas, “plasma”, in the direction of the Earth. And, “when the plasma reaches our planet, several atoms are excited”, explains astrophysicist Eric Lagadec. Thus, nitrogen gives a pink color to the sky and oxygen causes a fluorescent green. When a large coronal mass ejection occurs, it’s called a storm. For the president of the French Astronomical Society, the explanation is “very simple” : “The sun is very active at the moment and lucky or not, there have been ejections towards the earth. Which gives very beautiful things to see”.
The night show can last for hours. Those, also called auroras, are generally visible in areas close to the North and South poles, such as Alaska or Norway. They can be observed – more rarely – in other regions. The astrophysicist also claims that the celestial event has no connection with climate change.
In France, the auroras are observable approximately every ten years, provided that the solar eruption is strong enough and oriented in the right direction. The countries of the Far North record up to several hundred per year. The phenomenon usually lasts “a day or two days, depending on the size of the cloud”, explains Eric Lagadec.
It is therefore possible that this phenomenon will again be visible overnight from Monday to Tuesday. According to the expert, “a priori this episode is at the end but it will depend on the orientation of the magnetic field”. As usual, he advises spectators to get as far away as possible from light pollution and take the time to accustom their eyes to the darkness.
However, even if no aurora borealis were visible on the night of Monday to Tuesday, it would still be worth looking at the sky. “Tonight could be the occasion to see shooting stars, Venus and Mars. It is also an opportunity to say goodbye to the Eastern star which is gradually disappearing., enthuses Eric Lagadec. Another notable phenomenon this Monday evening in France, spotted by the scientist with humor: “the big pot” planned by opponents of Emmanuel Macron on the stroke of 8 p.m.
Update : at 1:15 p.m., with the addition of reaction from Freed by Eric Lagadec.