The Sun is very active over the last several weeks, and there are more and more sunspots born on its surface. Many of them appear on the other side of the Sun and then they are rising on the eastern edge of the Sun disc and travel across. Sun rotates for about 25 days, so a full path across the disc takes about 12 days to complete, but, of course not all sunspots will survive this, and also there may be some new spots that will be born just in front of us.
In the image above a large group of sunspots is presented, that are moving towards the Solar disc center. After enlarging the image solar granules can be noticed – they are large convection cells in the Sun’s photosphere. A typical granule size is between 1000 and 2000km.
Below this sunspot group, there is a large sunspot AR3310 that is presented in the image below. The complex structure of this sunspot’s shadow and center can be noticed in this image, but is better visible in the next image captured at a longer focal length – so also the image scale is larger, and the resolution was limited by atmospherical seeing (turbulences).
The image of the Earth was added for size comparison.
Sunspots are dynamic features and they constantly change. Not only the size and the shape but also the inner structure evolves. Plus there are many smaller changes in the Sun’s photosphere near the sunspot groups because magnetic field changes are quite strong in that area.
The next image shows how the area around the AR3310 sunspot varies during about six hours. Many changes may be observed in the sunspot itself, but also in the area around it.
Next image presents sunspots 3302 and 3305 – their lower number indicates that they were discovered earlier. They are now getting closer to the western Solar disc edge and will disappear soon. But they may survive the travel across the other side of the Sun and may get back to us after two weeks. And they will look different then – that’s for sure.
The last images present sunspot groups 3315 and 3319 in the following days. You can see how the groups evolve, and the last image presents changes in the 3319 that happened during one hour only.
Image technical data:
Date: 2023.05.21-31 Location: Nieborowice, Poland Telescope: Celestron SCT 8" with ND5 filter Camera: ASI290MM with Ha 35nm filter or Baader Solar Continuum filter Mount: Celestron AVX Exposure: 100 out of 2000 frames stacks at 10ms (2000mm focal length) and 16ms (3000mm focal length) Conditions: seeing medium-good