Sunspot back: "Exciting"

The space
The sunspot is back – can bring a new solar storm

Martina Karpmyr

Published 2024-05-29 23.24
 

After a solar storm, it may be possible to see the northern lights in the sky. Photo: Johan Nilsson / TT

On May 10, an extreme solar storm hit Earth – the strongest in 20 years.

Now the same active area is on its way back, according to researcher Peter Wintoft.

- It's really exciting, he says.

That an active region on the sun survives for 27 days is not quite common, according to Peter Wintoft. He does research at the Institute for Space Physics (IRF) and is responsible for Sweden's regional warning center for space weather.

But now it has happened. The active region on the sun that in early May produced the strongest geomagnetic storm in 20 years is visible again in the images that Wintoft and his colleagues follow.

And soon the area is once again directed towards Earth. And there is a risk that there will be another solar storm.

- That they live for 27 days, it's not quite common, but it happens. It's very exciting, he says.

During a solar storm, a powerful burst of energy occurs on the sun, consisting of radiation and particles. Storms that reach Earth can produce auroras in more places than usual, but can also affect power grids, communication networks, satellite systems and radio communications.

During the last extreme solar storm, Svenska kraftnät was on high alert.

Able to follow the area from the back of the sun

Since the area was aimed at Earth last time, the researchers at IRF have been able to follow the area with the help of special instruments. They measure the sun's vibrations so that scientists can see what is happening inside the sun, much like an ultrasound.

- So we were able to follow the area on the back side of the sun and saw that it was on its way back again, says Peter Wintoft.

On Monday, the researchers saw a large eruption from the area – both a so-called flare eruption and a so-called coronal mass ejection. However, it had no effect on Earth.

- If it had been aimed at the ground, it would have been a different matter.

 

Solar storms occur when two oppositely directed magnetic fields are brought together. Photo: AP

Could be another storm

In a few days, around June 2 or 3, the area is expected to be directed towards Earth again.

Whether the area continues to be as active or whether it fades in strength cannot be predicted, according to Peter Wintoft. But there is a risk that there will be another solar storm, which could have an effect on Earth.

- It is an interesting area and we have our eyes on it. 

FACTS

What is a solar storm?

• A solar storm is a powerful burst of energy consisting of charged particles or radiation.

• Solar storms that reach the Earth affect the Earth's magnetic field and the particles can cause gas molecules in the atmosphere to glow so that the aurora borealis is formed.

• Technically, the solar storms affect the power system by creating currents of several million amperes up in the ionosphere. These create a magnetic field which in turn creates a small potential difference - which drives a direct current, in extreme cases up to over 100 amps, in our directly grounded power system and this can cause problems.

• In the event of a solar storm, disturbances may occur in signaling systems and in the electricity grid. It can also cause corrosion in pipelines and disrupt the electricity supply for train traffic.

• In concrete terms, you as a private person can be affected by a power outage, or that your GPS does not work as it should.

Facts: Swedish power grid, MSB and IRF.