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Ursa Astronomical Association

Quiet aurora arc - 15.4.2018 at 01.52 Mustasaari Observation number 72994

Visibility Unclassified

Tommi Järvilehto, Vaasan Andromeda

Brighter northern lights arc than yesterday. The astronomical darkness is over, but the darkness is still enough when the moon is gone. Visually, the Milky Way was visible. Pretty restless atmosphere. The stars twinkled a lot.

A panorama assembled from individual exposures of five images.

Edit: new version for the first image. Panorama reassembly, horizon straight, noise reduction with DFine2.

More similar observations
Additional information
  • Aurora brightness
    • Dim auroras
  • Observed aurora forms
    • Arc info

      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.

  • 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.

Technical information

Sony a7, Samyang 14mm crop glass. f / s, 8s, ISO6400. Lr, DFine2 processing.

Comments: 1 pcs
Timo Alanko - 15.4.2018 at 15.59 Report this

Mainio suoritus! Vähän yökuhkimiseksihan tuo jo menee :)

Valaisevia yöpilviä sitten varmaan jatkossa.

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