Astrophoto of the month - April 2022 - Sunspots

The solar activity

A solar cycle lasts approximately 11 years, during which the solar activity first intensifies then weakens. In reality the solar activity is a set of phenomena linked to the changes of the Sun’s magnetic field. These phenomena are mainly the changes of the sunspots in shape and size, but protuberances and solar flares belong here as well. At the beginning of a solar cycle only a few, small sunspots can be observed, however in the middle huge and complex groups of sunspots float on the surface of the Sun, and solar flares become more frequent and stronger.

The 25th solar cycle was believed to be weak

Each solar cycle is different. Some are extremely intense and some show little solar activity. Astronomers know this from the systematic observation and comparison of the cycles since the first half of the 19th century. The current 25th solar cycle was initially predicted to be weak by astronomers, but the Sun has refuted this, and the intensity of solar activity has increased much more than expected over the past year. Larger and more extensive groups of sunspots appear one after the other.

The sunspots 2975 and 2976

Sunspots marked as 2975 and 2976 are also the messengers of the intensifying solar activity. They were created by a powerful magnetic field that bursts up on the surface of the Sun through the dark part of the sunspots, the so-called umbra. The magnetic field reduces the density of the plasma, so the surface of the Sun is slightly colder there than the average and therefore emits less light. The umbra is surrounded by the fibrous penumbra, which is the transition between the normal granular sun surface and the sunspot.

The 30 cm solar telescope

The image was taken by László Francsics from Fejér county, Hungary on March 22nd, with a 30 cm solar telescope that was specially designed and built for photographing the Sun. The telescope filters sunlight in a special way, so that the focused sunbeams do not ruin the image capture devices.

It is strictly forbidden to look into the sun with a telescope or take pictures without proper solar filters and protection equipment!