jmccance
Tim Bray 🇨🇦“Photographer Spends Night on Freezing Mountain to Capture Rare Triple Galaxy Arch” - astonishing photo and interesting how-it-was-done narrative.
Dr. Juande Santander-Vela@timbray what he calls Gegenschein is called Zodiacal Light in astronomy, and Brian May (yes, THAT Brian May) did his doctoral thesis on it…
AhimsaI think it says they're different forms of the same thing. Text from the gegenschein entry is a bit clearer:
"Like zodiacal light, gegenschein is sunlight scattered by interplanetary dust ... Gegenschein is distinguished from zodiacal light by its high angle of reflection of the incident sunlight on the dust particles."
https://en.wikipedia.org/wiki/Gegenschein
I don't know for sure, just sharing what's on Wikipedia! Remembered zodiacal light from Artemis mission photos so I looked it up. 😊
@ahimsa_pdx OK, in both cases they are light reflected from interplanetary dust essentially in the disc where planetary formation happened in our solar system.
The main difference is that you can see that reflected light either at an angle from the sun, and then it’s zodiacal light, or back reflected directly from the sun behind the observer.
In any case, it’s always material (mostly) in the plane of the ecliptic, which means you have the constellations of the Zodiac in that shine, regardless of mode.
Elias Probst@timbray The original blog post by the photographer with higher res pictures:
https://blog.angelfux.com/p/triple-arch-at-4200m-matterhorn
https://blog.angelfux.com/p/triple-arch-at-4200m-matterhorn
glasspshr
Kevin Russell@glasspusher @eliasp @timbray @MrManor
First, wonderful post, astounding image.
I would also love a lower resolution movie of the photos being added to the composite, including the movement of the sky to get into position for the final relationships shown.
Klaus Vink Slott@timbray
What an amazing picture and story! My mind is struggling to comprehend what I'm looking at. Is it 2 time lapses stitched together?
What an amazing picture and story! My mind is struggling to comprehend what I'm looking at. Is it 2 time lapses stitched together?
Clyde Davidson@timbray Pure AI. There are no galaxies that are together like that NOR are visible from Earth like that!
Matthew NewellHmm. It's our galaxy - twice but different parts; it's all explained in article . And the faint loop is explained above.
One of the dangers of AI (like deliberately faked news) is we start to see false positives everywhere
Avner@lugh_clyde read the article. It goes into depth on how that image was produced.
@lugh_clyde In these particular times, you really shouldn't throw that particular accusation around.
Ditol@timbray
Actually, it is quite the opposite: in these particular times one has to prove a photo of a magnificent phenomenon, a result of hours and days of hard work, is not some AI slop. I just saw a video of another "magnificent phenomenon" two weeks ago, fortunately it was clearly recogniseable as AI. So when I saw this photo, I immediately thought this was another AI slop image. In my mastodon timeline. I hate it. Then I read the blog article. But since the internet is full of fake blogs written by AI agents, I am still only 95% convinced. I hate the time we live in.
xyhhx 
@ditol look up "milky way double arch", and you'll see other similar photos: https://earthsky.org/todays-image/best-milky-way-photos-of-2025/
@lugh_clyde likes to be an annoying reply guy
Spocko