Contact information

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

Ursa Astronomical Association

Quiet aurora arc - 28.7.2021 at 23.31 - 28.7.2021 at 23.41 Plumas, Kanada Observation number 108239

Visibility II / V


The time is in Central Daylight Savings time.  The data told me that there was aurora activity, but it took so long for it to get dark I didn't really see anything.  I took some milky way photos and turned around to see a bit of activity.  I didn't take many photos as it was very minimal activity, but when processing I saw an arc that looks like STEVE.  I set the photos aside as I really couldn't tell for sure.  When I looked at them today, I realized that there are pickets below the pink arc in 3 photos (0801-0803), so now I am assuming it was a STEVE.  I have seen this faint arc in many photos and wondered if it was a STEVE.  It is difficult to determine when it shows up against the main aurora.  I believe that STEVE is there way more often than we can see, in this faint form.


More similar observations
Additional information
  • Aurora brightness
    • Very dim auroras
  • Observed aurora forms
    • STEVE-arc info

      STEVE (Strong Thermal Emission Velocity Enhancement), Pink, radial aurora-like arc  . The STEVE arc is seen clearly separated from the main aurora arc of the northern sky. It forms a long and narrow west-east aligned, usually dim form. It does not belong to traditional auroras as a phenomenon, but may appear same time with them. Occasionally there may also be a green, "toothed" band called ”picket fence” at the bottom of Steve.  

      Riku Talvio, STEVE
      Photo by: Riku Talvio

    • Picket fence info

      A picket fence is a green form of aurora (northern lights) with short vertical beams.

      Picket fence often occurs under the purple-gray STEVE arc, but can also be an independent green radial arc.

      In the picture, the board fence is shown in the upper right corner under the STEVE arch. Photo by Sirpa Pursiainen

      The picket fens gets sometimes mixed up with normal green belt with rays. In Picket Fence, the individual rays are clearly separated from each other and the arc of the rays is clearly separated from the rest of the northern lights. The fences of the fence also do not form a single curtain extending up to the pole of the sky.

      Picket fence can also occur independently without a STEVE arc. The picture shows very well how the Picket Fence is separated from the rest of the northern lights and does not expand upwards. Photo by John Andersen

Comments: 1 pcs
Emma Bruus - 10.8.2022 at 09.55 Report this

Yea this looks like STEVE, although the arc is more diffuse and dimm than one would expect.

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.