The Active Solar Disc in Broadband White Light 24_04_2025

 

Sunspot Groups on the Solar Photosphere 24_04_2025 during Solar Maximum - 66mm ED Altair Lightwave Refractor with Baader Film White light Objective Filter. Capture Camera: QHY5iii462c CMOS Planetary Video Camera with IR cut Filter doble  stacked with a Meade Optical red light filter. Images: Credit: Kurt Thrust.

"The Solar Sunspot Cycle, also known as the solar cycle, is an approximately 11-year cycle in which the number of sunspots on the Sun's surface increases and decreases. Sunspots are dark, cooler regions on the Sun's surface caused by intense magnetic activity. This cycle influences solar radiation, space weather, and even Earth's climate."

Solar Disc imaged with the Seestar S30
- Fighting above its weight in less than optimum conditions.

Key Features of the Solar Cycle:

• Solar Minimum: The period of the fewest sunspots. The Sun is relatively quiet.

• Solar Maximum: The peak of sunspot activity. The Sun is more active, with more flares and coronal mass ejections (CMEs).

• Duration: The full cycle (from one minimum to the next) lasts about 11 years, but it can range between 9 and 14 years.

What Drives the Solar Cycle?

The solar cycle is driven by the Sun’s magnetic field, specifically a process called the solar dynamo:

1. Differential Rotation: The Sun rotates faster at the equator than at the poles. This twists magnetic field lines over time.

2. Convection Currents: Hot plasma rises and cool plasma sinks in the Sun’s outer layer, further distorting the magnetic fields.

3. Magnetic Field Reversal: About halfway through the cycle (around solar maximum), the Sun’s magnetic poles flip. This magnetic reversal is part of a 22-year magnetic cycle—the sunspot cycle is half of that.

Why It Matters:

• Impacts satellites, GPS, and radio communications.

• Drives auroras near the poles.

• Can pose risks to astronauts and space missions.

• May influence Earth's climate on longer timescales."  

-Generated by ChatGPT open AI

"For the last few days, the weather has been difficult for 'Astrophotography' from the Jodrell Plank Observatory located at the UK's most easterly point in Lowestoft. Both during the day and night there has been persistent high level hazy cloud which has made capturing fine detail impossible. Recent auroral alerts lead us to believe that the Solar photosphere would have many visible sunspot groups, so even with poor visibility, we thought we would take a look. We imaged the sun across the full range of visible wavelengths ( called Broadband or white light imaging) using objective-lens mounted rejection filters which make the process safe. We imaged the Sun using our EQ mounted 66mm ED refractor and our Alt-Az mounted Seestar S30. We were reasonably and positively surprised at the results. The Sun is our nearest star and although it seems a constant unchanging companion, it is a dynamic system of turbulent and hot gas, compressed to a roughly spherical shape by gravity and prevented from collapse by the outward pressure of nuclear fusion at its core. One day, far in the future, when the Sun runs out of Hydrogen and Helium to fuse, it will first swell and cool to become a Red-Giant star and then end its days as a fading Planetary-Nebula with a White dwarf star at its centre - similar to M27 in the constellation Vulpecula". - Joel Cairo CEO of the Jodrell Plank Observatory.

Planetary Nebula M27
imaged from the Jodrell Plank Observatory