
© Andy Stables/spaceweathergallery.com
Noctilucent clouds (NLCs) have been spotted over Poland, Czech Republic, Canada, and Scotland, among other countries, on May 25 and 26, marking an early start to the northern hemisphere's 2021 NLC season. The clouds are rapidly intensifying. In only four days since the clouds were first seen, their coverage of the Arctic has multiplied 10 times.
On May 26, 2021, photographer Andy Stables captured NLCs over Milovaig in the Isle of Skye, Scotland. "The NLCs got stronger and this was taken at 00:47 UTC (01:47 LT)," Stables said.
The electric-blue rippers "were clearly visible to the unaided eye," he added. "This is the earliest I have ever seen them here in Scotland."
Dr. Tony Phillips of spaceweather.com described the phenomenon as unusual, noting that the NLCs are already forming even though it is only May. Other witnesses are able to see the clouds from the ground.
"NLCs are Earth's highest clouds," said Dr. Phillips. "Seeded by meteoroids, they float at the edge of space about 83 km (52 miles) above the ground."

© Tomasz AdamEarly NLCs captured in Krakow, Poland, on May 25.