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Rays at sunset

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Anding's picture
Last seen: 10 months 1 week ago
Joined: 08/03/2014 - 04:09
Rays at sunset

Photographed August 27th, 2019 looking towards the sunset, Hong Kong harbour.  I'm not sure what the atmospheric cause would have been but am interested to hear any speculations!

The photo was taken by an iPhone 6 and is unprocessed.  Happy to share the full size image if requested.

Xilman's picture
Last seen: 55 min 10 sec ago
Joined: 24/03/2018 - 15:17

Looks like shadows cast by some objects (clouds near or below apparent horizon  perhaps) on the regular forward-scattered sunlight.

Grant Privett's picture
Last seen: 9 hours 55 min ago
Joined: 28/12/2014 - 18:30
Bumpy horizon

Commonly termed, crepuscular rays.....

Peter Anderson's picture
Last seen: 6 days 8 hours ago
Joined: 21/11/2015 - 23:34
Crepuscular rays

Spectacular when they stream right across the sky and converge on the anti-solar point (see attached - leaving Bora Bora)

Last seen: 5 days 19 hours ago
Joined: 15/03/2016 - 10:15
Twilight sky

The phenomenon has been known for a long time.

An old description of the phenomenon can be found here:

SAO/NASA Astrophysics Data System (ADS)

Title: Sur les rayons lumineux divergents

Authors: Mascart, J.

Journal: Bulletin de l'Observatoire de Lyon, vol. 9, pp.151-155

Bibliographic Code: 1927BuLyo...9..151M

Since light pollution has erased the stars from the sky above my city, I now study atmospheric phenomena at twilight. I would appreciate some photographs of the sky at sunset or sunrise taken from your residence. If you want, please contact me at this address.



L'Aquila city (Italy)