After a two year long no-show, the mysterious 28° arc finally makes its comeback in China, in a very dramatic way.
Between Aug 7 and 14, the arc was observed four times in three provinces, setting a new record.
Aug 14, Ningbo, Zhejiang Province
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| Photographed by LI Shengyu. Single exposure with no processing. Shown with permission. |
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| BGR and B-R versions of the stacked image. |
Very high quality set of capture by LI Shengyu. Stacking, BGR and B-R processing reveal the arc's weird sunvex comma shape, reminiscent of the 2020 Pu'er display ( https://thehalovault.blogspot.com/2020/09/mysterious-sunvex-28arcs-in-yunnan-china.html ).
Aug 13, Xi'an, Shanxi Province
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| Photographed by Aphelius. Shown with permission. |
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| Enhanced by Aphelius. Shown with permission. |
Seasoned sky watcher Aphelius sets China's northernmost (35°N) 28° arc sighting record with his brilliant Aug 13 observation. Xi'an is geographically considered a Northern China city, which means the 28° arc finally makes its debut in Northern China. It remains to be seen how much more north it can push in future.
Aug 10 and Aug 7, Renhuai, Guizhou Province
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| ZHANG Zhengqiang's second observation on Aug 10. Mobile phone photo. Shown with permission. |
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| BGR processed version. |
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| ZHANG Zhengqiang's first observation on Aug 7. Mobile phone photo. Shown with permission. |
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| BGR processed version. |
Yet another new record, ZHANG Zhengqiang witnessed a repeat event merely two days after his first observation on Aug 7, from exactly the same location! The two displays almost look identical. Atmospheric condition during those few days must have been remarkably consistent.
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At the time of writing, there's still an ongoing odd radius plate arc outbreak in Southern China, which has lasted more than a month and shows no sign of stopping. Plate arcs are spotted almost everyday in (mostly) Southern China since late June. We shall reach well over 50 odd radius days in 2022. More 28° arc occurrences are likely on the way if the outbreak continues.
Jia Hao
Chinese halo network be praised for recording this 28 arc landslide. On how many days they were seen? Maybe you could actually list the days? It would interesting data.
ReplyDeleteThanks for the compliment Marko. So far we have them on Aug 7, 10, 13, 14, 16, 21, 22, 23, 24, 26 and 28, so that'll be a total of 11 days.
DeleteJI Yun is maintaining a map with all the 28° arc sighting locations marked. You can view the latest (as of Aug 26) at: https://weibo.com/2539943557/M2Sbnfps6
Thanks, that's nice to know. It is good times be alive as a halo observer. The Chinese are well placed to provide cruicial information on the Lascar halos mystery. Perhaps the 28° arc shape issue will be settled definitely – in possibly not so distant future – by another stacking set. Likewise, we in Finland, too, have those keys in our hands thanks to the 28° halo surface displays and the possibility to have a look at the crystals.
ReplyDelete(I see I commented here on the wrong post, was supposed to be the next one.)