Mars - My first picture 2022

My first close-up picture from Mars this year. The red planet is currently 0,57 AE away from Earth and is 97% illuminated. The angular diameter is about 16,4".

Setting: TAL200K f/8.5 with ASI224MC and ADC, Barlow x2

Software : SharpCap 4, AS3! (25% stacked), CS4 and DeNoise AI

Calculating Limb Darkening Coefficient

I calculated the Limb Darkening Coefficient from the Linear Limb Darkening law assuming a plane-parallel solar atmosphere.:

As a base, I used a picture from the solar disk taken during the recent solar eclipse with an OIII filter (500nm). Using ImageJ software I was able to plot the intensity (limb darkening) graph by retrieving the gray intensity data per pixel. Using above formule, I calculated the Linear Limb Darkening coefficient (LDC). To calculate the LDC, I took the average LDC's of the radius between 0,9 and 0,3 . This results in a LDC of 0,22 (500nm)

I put this data together in a graph which combines the intensity graph from ImageJ and the theoretical derived graph with a LDC of 0,22.

Discussion:
In the literature I found LDC's  of around 0,8 (eg. Dias-Cordoves see this link)  

Conclusion : my LDC calculation is not really near the ones published in different studies. 

See also interesting LD calculators like the one for the James Webb Telescope. See this link

Dynamic of Sunspot group AR3141 and AR3145

Picture of sunspot group AS3141 and AR3145 on November 11 and 12.

 

Sunspot AR3141 - CaK and White light

 

Sunspot AR3141, AR3140 and AR3145 observed on November 12, 2022. Sunspot AR3141 not only photographed in White Light but also with CaK filter.

Setting : TAL200K f/8.5, ND3.8 filter, CaK filter, ASI290mm, Barlow x2

Software : SharpCap4, AS3! (50% stacked), IMPPG, CS4

Sunspot AR3141 - Light Bridges

Some high clouds but still I was able to make some pictures of Sunspot AR3141 (and AR3140, AR3145). Sunpot AR3141 is a complex sunspot with an beta, gamma, delta configuration. 

The sunspot has also a couple of bright light bridges.

Setting: TAL200K f/8.5 with ASI290MM and ND3.8

Software: SharpCap 4.0, AS3! (25% stacked), IMPPG, DeNoise AI and CS4

Moon and Jupiter

Jupiter north of the Moon with Golden Handle.

Halo 22° and Circumzenithal Arc

Around midday, the sun was surrounded by a halo 22° and a faint circumzenithal arc.