Sky spectacle in fast motion This is how beautiful the auroras shone over the Matterhorn

A rare celestial spectacle appeared twice over Switzerland on Wednesday: auroras colored the night sky - including over the Matterhorn.

The northern lights appeared twice in Switzerland on Wednesday. The first time the play of colors appeared in the early morning, the second time the pink veils of light appeared in the evening after dark.

On webcams such as the one on the Jungfraujoch, pink veils of light could be seen in the Swiss night sky to the north on Wednesday evening. It was reported in advance that the chances of seeing the Northern Lights were even better than the previous night.

And auroras also transformed the night sky above the Matterhorn into a spectacle of color.

Strongest solar storm of the year so far

According to the US weather agency NOAA, the strongest solar storm of the year so far occurred on Tuesday. The ejected particles reached the Earth's atmosphere on Wednesday evening. Auroras occur when such charged particles from space enter the Earth's atmosphere.

The so-called KP index provides an indication of the probability of aurora sightings. Higher KP values were predicted for Wednesday evening than for the previous night.

The auroras visible in Switzerland early Wednesday morning were also triggered by solar storms on Sunday and Monday, as the Federal Office of Meteorology and Climatology MeteoSwiss explained at the request of the Keystone-SDA news agency.

The auroras were visible on Wednesday morning between around two and six o'clock in almost the whole of Switzerland. On the mountains, in the lowlands and on both sides of the Alps - and on webcams on the Rigi and Säntis, for example - the pink veils of light were visible. On the Central Plateau, however, visibility was limited in some areas below 500 meters due to fog, according to MeteoSwiss.

Sun particularly active at the moment

Northern lights are generally rare in the Alpine region. However, it is no coincidence that last year and this year, auroras are particularly frequent far to the south.

The sun follows an approximately 11-year sunspot cycle. The more sunspots, the more active the sun. We are currently at the maximum of this cycle. As a result, solar storms become more frequent and more intense, which also increases the chances of seeing auroras, even in our area.

But there is also a portion of luck involved. Because for the auroras to actually be visible in Switzerland, their timing has to be just right. When the charged particles of the so-called solar wind enter the earth's atmosphere, the sky must be dark and as cloud-free as possible for auroras to be visible.

According to MeteoSwiss, the impression that auroras are currently occurring more frequently is probably not only due to the current sunspot maximum. They can be observed more easily with the many cameras and are therefore more present in the media than in the past.

Oxygen turns lights green

When the solar wind reaches the Earth's atmosphere, the charged particles are generally deflected by the Earth's magnetic field and directed towards the polar regions. This process causes the particles to reach the poles.

Once the charged particles reach the atmosphere, they collide with the gases in the atmosphere, mainly oxygen and nitrogen. These collisions release energy and light. The stronger the solar winds, the more southerly the northern lights are visible.

The color of the Northern Lights depends on the type of gas particles with which the charged particles interact in the atmosphere and the altitude at which these interactions occur. Green northern lights are often caused by interaction with oxygen in higher atmospheric layers, while red or violet colors can be caused by interaction with nitrogen.

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