Wednesday, 27 August 2025

Sub-Liljequist and probable 'sub-Liljequist Blue Spot' in high cloud above China

 


The sub-Liljequist 'Parhelion' in high-clouds is rare. On August 14, 2025, a user '太平洋蓝藻'(ID: 516836436) from ' Bilibili.com'(a polular vedio website of China) captured the first record of this event in China during a flight over the Yellow Sea. the sub-Parhelic Circle and sub-120° Parhelion were captured at the same time.




What makes this particularly remarkable is that on left of sub-Liljequist 'Parhelion' in the photograph shows a distinct blue tint, suggesting the possible presence of 'sub-Liljequist Blue Spot'. Pinson HUANG from the Chinese halo watching community was the first to identify this possibility and made the initial simulations. I refined the simulation parameters based on HUANG's work, and the results showed a good alignment with the photograph. SUN Hao Xuan(孙浩轩) and Jing Xiang from the Chinese halo watching community assisted in image authorization and joined in the related research process. KiloNova(千新星), SONG Xi Pei and QIAN Kun from the same community provided crucial information in the analyses of flight data and lens characteristics.

 




The photograph was taken at 16:43:26 (UTC+8). Based on the CZ5855's flight information(N37.96, E122.98) retrieved from https://flightadsb.variflight.com for that specific time, it can be further concluded that the solar altitude was 22.3 degrees.


The unevenness of cloud layer should be considered as the cause of the unevenness of the sub-PC, but some simulation results quite support the existence of the sub-Liljequist.


Friday, 9 May 2025

Halos of Venezuela

South America is pretty much a blank slate what comes to halo enthusiasm, so it is encouraging when we got contacted from Venezuela by Franklin Fernández, who had written an article presenting the best displays captured in his country. Judging by the random big displays that have popped up from different corners of South America over the years, there is reason to think the continent as one of the better areas for halos, and now the Venezuelan displays Fernández has scoured from the internet add credence to this notion.

What is more noteworthy is that the best displays are concentrated in the western part of the country which is where the Andes mountain chain ends. This gives more weight to what some of us may have already thought, that the curse of the equator is cancelled by the Andes. Unlike in the Philippines where I have been observing, or Singapore of which halo scene I have heard from Jia Hao, all-sky displays must be a regular occurrence along the tropical segment of the Andes chain and presumably sun pillars are not such rarities either. And we don't know what kind of odd radius jewels there might be lurking as these shows don't tend attract so easily the attention of the uninitiated.

Franklin's article is available in Academia.edu and Scribd. He will keep adding displays to it as they come and says the document has already created buzz. Could this be the start of Venezuela and eventually the continent's other Spanish speaking countries waking up to halos? All prospects are that a dedicated observer, in particular along the Andes chain, would be in for reaping it big.

(The display above was captured by TikTok user danny3461 on 6 October 2024 in Macoa near the city of Machiques at the west of the country. In my hastily made stitch the parhelic circle is full despite the large gap on the right. The show was documented by a handful of other people as well. See also the impressive high sun display on X of an unknown date in Caracas)

Thursday, 20 March 2025

A grand Bottlinger's rings in diamond dust (2025-Jan-12, China.)

 A spectacular event of Bottlinger's Rings occurred on January 12, 2025, in Hemu(禾木), Xinjiang, China. For China, this was the first time the phenomenon was observed in diamond dust (rather than being captured from high-altitude aircraft). 'Javen嘉文儿', a user from the video website 'bilibili.com', directed his photography team to captured extensive footage. We are permitted to share the related files here.





vedio here

 

Footages show a solar elevation angle of 11 to 12 degrees. The lack of ice crystal sampling is regrettable, and it is hoped that valuable ice crystal samples can be obtained the next time such event occurs.


The original web link: https://www.bilibili.com/video/BV1jKKweuEQG/?share_source=copy_web&vd_source=e1764a76e81b36e4cb1d6f24f1f6a9ee

 

(We'd like to thank: Sufflection_, Jingxiang and Danyang(佩佩), for their assistance in related communication.)