Blog post

Researchers on Expedition to the Antarctic see fantastic light phenomena

Published on
September 1, 2013

The researchers on Expedition to the Antarctic see beautiful halos with sundogs. Ice crystals in the atmosphere create these phantastic light phenomena.

Photo: Full halo with clear sun dogs and light pillar.

With air-temperatures around -20° Celcius, we observe fantastic light phenomena above the sea ice of the Weddell Sea. Beams of sunlight are broken and reflected in specific ways depending on shapes and angles of ice crystals in the atmosphere. The most common phenomenon is a rainbow like circle at an angle of 22° from the sun. Such rings are known as ‘halos’ derived from the old Greek word for a circular threshing floor. In the inner halo, under the right conditions, two so-called ‘sundogs’ are visible plus a light pillar above.

Outer halo

Only when the inner ring is strong, a second halo may be observed in an angle of 46° from the sun. And we could see it! To catch it all in a single picture one needs a stronger wide-angle lens on the camera than I have, so it had to be captured in half an image. The outer ring was much weaker and lacks the ‘dogs’ but ended as a weak rainbow in the sea ice.

Triplicate sunrise

This morning it became certain that I had to write a blog about this. The first view through my cabin window revealed a beautiful sunrise in a narrow clear band of sky between the sea ice horizon and a narrow band of clouds. It took me a while to realise I was viewing sunrise in triplicate! So I dashed outside to take a picture while shivering in the cold. I had to share such beauty. Although at this position of the sun there was no clear halo, the two sundogs were strongly present. What a fantastic view! Like this, even a one-track minded biologist can be totally dazzled by physical phenomena.

Jan Andries van Franeker

PS first successful SUIT hauls show krill and diversity of life under ice. More news later.

wur_forum_reactions_wrapper for object 43 of type wm_language nl_gx_webmanager_cms_core_implementation_languageimpl 5

  • G.K. Verboom

    Ik heb zojuist een foto gezien van drie regenbogen. Twee lopen parallel, dus eerste en tweede en vaag een derde halo, maar is nog een vierde lichtsterke halo die niet parallel loopt met de andere en zelfde de eerste van de andere set snijdt. Betekent dit dat de regenbogen op grote afstand van elkaar en in verschillende luchtlagen zijn ontstaan?

    • A. Talsma

      Op bericht / reactie G. K. Verboom;

      Heb aantal foto’s vanuit West-Terschelling genomen deze week met betreffende verschijnsels

      Probeer ze op te sturen

  • Arnold de Lange

    Dit soort foto´s doet mij altijd meteen denken aan de lichtverschijnselen of `hemeltekens` die de bemanning op de schepen van Willem Barentsz en Jan Cornelisz Rijp zagen, tijdens hun zoektocht naar de noordoostelijke doorvaart in 1596...

  • Hanneke van Ommen

    leuk hoor om zo van jullie te zien en te horen!

    groetjes Hannek

  • Liesbeth Wieberdink

    Wat prachtig!!! En vogels tellen vanuit eennhelicopter lijkt me ook geen straf.

    Heel veel succes met jullie werkzaamheden en geniet van al het moois dat er te zien is.

    Liefs Liesbeth