Sun in helium D3 coronal hole
Taken by Richard Schrantz on October 17, 2025 @
Nicholasville, Kentucky, USA
Click photo for larger image
| |
Camera Used: Unavailable Unavailable
Exposure Time: Unavailable
Aperture: Unavailable
ISO: Unavailable
Date Taken: Unavailable
|
|
| More images
Details:
Yesterday, I noticed a large coronal hole on the sun as shown by the Solar Dynamics Observatory satellite image at 211 Angstroms (extreme UV).
I was able to indirectly image this coronal hole with my 102mm f/7 spectroheliograph by imaging the helium D3 line (just to the blue side of the sodium doublet in yellow light). Helium details on the sun are caused by the super-hot corona shining extreme UV down from above. Less EUV emitted in a coronal hole area means less helium detail below. EUV cannot be imaged from earth's surface (thank goodness), so this is one way to detect coronal holes from earth!
Aren't SHG's cool? Yes.....yes they are.
Photographer's website:
No URL provided.
|
|
|
