Newest observations

Contact information

Skywarden,
Ursa Astronomical Association
Kopernikuksentie 1
00130 Helsinki
taivaanvahti(at)ursa.fi

Ursa Astronomical Association

Active aurora band - 17.9.2021 at 23.00 Ulvila Observation number 101316

Visibility III / V


Northern lights over Pori on 17.9 at about 11 pm The sky was almost cloudless at first, but soon covered with a cloud curtain.



More similar observations
Additional information
  • Aurora brightness
    • Bright auroras
  • Observed aurora forms
    • Band info

      Bands are usually narrower, more twisty at the bottom, brighter, and more active than arches. Bands usually develop from arches.

      Bands can form J and U shapes, sometimes even full spirals. The corona can also arise from bands. Bands are a fairly common form of aurora.

      Aurora band. Photo by Merja Ruotsalainen.

      Aurora band. Photo by Matias Takala.

      Aurora band. Photo by Lea Rahtu-Korpela.

      Aurora bands. Photo by Lauri Koivuluoma.

      Aurora band. Photo by Matias Takala.

  • Colors with unaided eye and other features
    • Green auroras info

      Green, seen with the naked eye, is one the most common colors of the aurora. The green color is derived from atomic oxygen.

      Green auroras. Lea Rahtu-Korpela.

      Green auroras. Photo by Juha Ojanperä.

Send a comment

Comments are checked and moderated before publication If you want to contact the observer directly about possibilities to use these images, use the Media -form.

*

*

*
characters left

By sending in this comment I confirm, that I've read and understood the the observation system's privacy policy.