Quiet aurora arc - 12.9.2017 at 00.50 - 12.9.2017 at 01.09 Ikaalinen, Sisättö Observation number 66975

Visibility II / V

Heidi Rikala, Ursa (Helsinki)

Dim and very low northern lights. They didn’t have long to dance there - a huge mass of clouds rolled north. These repos could probably be waited for 3 hours.

This description has been automatically translated from Finnish. Click here to see the original text.

4 2

Additional information

Aurora brightness
- Dim auroras
Observed aurora forms
- Arc
  
  ARC The arcs are wider than the bands and do not fold as strongly. The arcs are normally neither very bright nor active.
  
  The arc is probably the most common form of aurora. When aurora show is a calm arc in the low northern sky it often doesn’t evolve to anything more during night. In more active shows the arc is often the first form to appear and the last to disappear.
  
  The lower edge of the arc is usually sharp but the upper edge can gradually blend into the background sky. As activity increases rays and folds normally develop, and the arcs turn gradually into bands.
  
  An aurora arc runs across the picture. Vertical shapes are rays. Photo by Atacan Ergin.
  
  Aurora Arc. Photo by Mauri Korpi.
  
  Aurora Arc. Photo by Anna-Liisa Sarajärvi.
  
  Aurora Arc. Photo by Matti Asumalahti.

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.

Newest observations

Contact information

Quiet aurora arc - 12.9.2017 at 00.50 - 12.9.2017 at 01.09 Ikaalinen, Sisättö Observation number 66975