Sol - 31 July 2020 - AR2768, AR2767 & Prom

[Hughsie]

Busy day today.

According to Spaceweather Live, AR2768 is coming around the north western limb. The large prominence is still doing its thing and we are soon to say good bye to AR2767.

Best 200 out of 1,000 frames stacked in AutoStakkert 2, initially processing in ImPPG and tweaked a bit in PixInsight.

I was out imaging the green channel for my Iris Nebula project last night and so removed the WO Z103 imaging scope this morning and swapped it out for my Lunt LS60THa adding the ZWO ASI174mm camera to capture today’s activity.

Thank you for checking in.

 

John

[MarkAR]

Lovely shots, that prom is huge!

 

[Debo]

A real whopper of a prom.

[Hughsie]

Does anyone know how we can find out how big it is?

[Merlin66]

With the attached overlay you can estimate positions and sizes of the proms.

 

RegleSolaire-v4b.pdf

[Merlin66]

Applying the grid to the Gong image:

It shows the prom height is greater than 200,000 Km! That's roughly 16 times the diameter of the Earth.

 

[Hughsie]

Thanks Merlin, this is brilliant.

Earlier today I brought the image up in Affinity Photo and used the rulers tool to measure the diameter of the disc. This came out at 28.12 cm so representing the diameter of the Sun at 1.3927 million km. Next I applied two further rulers to the tip and root of the prominence creating a right angled triangle with the prominence as the hypotenuse. This gave me two sides of the triangle at 2.57 cm and 1.69 cm. Using Pythagorus Theorum I calculated the length of the hypotenuse as the square root of the sum of the squared sides; 3.08 cm. So, if 28.12 cm is equivalent to 1.3927 million km then 3.08 cm is 152,543 km which is certainly close to what the overlay suggests.

John

 

 

Edited August 1, 2020 by Hughsie

[Merlin66]

I've prepared an English translation of the SolarRuler, which may assist.

 

SolarRuler-v4b_e.pdf