8 replies to this topic

[PrestonE]

Hola Everyone,

 

My associate ask a question that I cannot answer.

 

Is the Red color during a Solar Eclipse of the Prominces  due to the 

Hydrogen Alpha?

 

I am thinking not, but not really sure...thus, my question to you.

 

Image from Durango, Durango, Mexico today.

 

Robin???

 

Best Regards,

 

Preston

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[gstrumol]

Yes, I believe so. Prominences are not visible in WL images, whereas they are, well, prominent in Ha images. And the Ha line is in the red part of the spectrum.

[TOMDEY]

Red because it's Hydrogen Alpha, which is the transition between the 2nd and 3rd orbitals in the Balmer Series... the jump twixt 2nd and 4th we call Hydrogen Beta, between 2nd and 5th we call Hydrogen Gamma, etc., ad infinitum.    Tom

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[sharkmelley]

Visually (and to most consumer DSLR/Mirrorless cameras) the reason they appear pink is because of the H-alpha, H-beta and H-gamma emissions.

[robin_astro]

And not (predominantly) Helium as more than one NASA commentator said during their live coverage, though the famous orange He line which led to the discover of Helium is also visible in the chromospheric flash spectrum as here in 2006

 

http://www.threehill.../spectra_27.htm

 

Robin

[robin_astro]

Here is Lockyer's historic measurement of the spectrum of a prominence from 1868.

https://royalsociety.../rspl.1868.0011

The C and F Fraunhofer lines mentioned are H alpha and H beta and the line near the D (Sodium) Fraunhofer line is Helium leading to its discovery, along with Janssen and others who had also observed it a few months earlier during a solar eclipse but did not identify it as a new element

 

Robin

[PrestonE]

Thanks Everyone!!!

 

I will pass this information off to my friend Gustavo Cervantes Reyes in Guadalajara .

 

Very Best Regards,

 

Preston

[columbidae]

Visually (and to most consumer DSLR/Mirrorless cameras) the reason they appear pink is because of the H-alpha, H-beta and H-gamma emissions.

To me they looked orange (as well as in the photos my brother-in-law took).

 

 

And not (predominantly) Helium as more than one NASA commentator said during their live coverage, though the famous orange He line which led to the discover of Helium is also visible in the chromospheric flash spectrum as here in 2006

 

http://www.threehill.../spectra_27.htm

 

Robin

Do the relative intensities of the H-alpha and the 668+587nm He lines overpower the bluer emission spectra?  Or is there some weird color perception nonsense going on.

[robin_astro]

 

 

Do the relative intensities of the H-alpha and the 668+587nm He lines overpower the bluer emission spectra?  Or is there some weird color perception nonsense going on.

cameras can play tricks with colour balance but if you remove green from a continuous spectrum leaving the red and blue ends the result is a similar pinkish colour. Here for example in my reflectance spectrum of  the JWST sun shield and in the reflection from dielectric Johnson V filters

https://britastro.or...28ed4b0a22ce097

so that would suggest we are seeing a mainly a combination of red H alpha and blue H Beta, Gamma as Sharkmelly suggests with the orange He playing a minor part as in this snapshot from my 2006 flash spectrum video. (note the lines are not double, just poor focus)