Ha & CaK Sun 10th June 2024

[Maurice]

Hi

Attached are two images of the Sun taken this morning from Melbourne at Ha and CaK wavelengths.

ED100mm f/9 refractor + spectroheliograph + ASI 183MM camera.

Images reconstructed with Doug Smith's SHG Main software.
Best frames selected and stacked with AutoStakkert3!
Final deconvolution processing with Astrosurface.

Best 4 of 7 frames stacked for Ha
Best 8 of 16 frames stacked for CaK

Images reduced to 60% of full size and heavily compressed here.


It is getting harder to get good data with the sun so low in the North ATM..


Cheers
Maurice

[John W (John Wilkinson)]

Well done Maurice - lots of features to see. Good comparison with two wavelengths as well.
Regards, John W.

[foc (Ross)]

Great detail in your images of the many filaments and prominences in Ha. Makes quite an attractive Souvenir of this busy solar month. Nice contrast in the Ca image for these deeper layers

[morls (Stephen)]

Great images, really interesting.

I've got a very basic question about the Ca-K images...I can understand how the H-alpha wavelengths come about, but what is the source of Ca-K wavelengths?

Stephen

[Maurice]

Originally Posted by John W

Well done Maurice - lots of features to see. Good comparison with two wavelengths as well.
Regards, John W.

Thank you John.

Originally Posted by foc

Great detail in your images of the many filaments and prominences in Ha. Makes quite an attractive Souvenir of this busy solar month. Nice contrast in the Ca image for these deeper layers

Thanks Ross. It has been quite an active solar month.

Originally Posted by morls

Great images, really interesting.

I've got a very basic question about the Ca-K images...I can understand how the H-alpha wavelengths come about, but what is the source of Ca-K wavelengths?

Stephen

Hi Stephen


As I understant it,the absorption of the photospheric light by the ionized calcium atoms present in the chromosphere is the source of the Ca-K wavelengths.
Furthermore, the central part of the Ca-K line (the K3 portion) is where the ionized calcium atoms are higher in the chromosphere at about 2000km above the photosphere with the K1 at about 600km and K2 between about 700km and 1500km above.


I can recommend this link for a better explanation than I could ever give:


http://www.astrosurf.com/spectroheli...0k-line-en.php


Cheers
Maurice