Talk:Circumhorizontal arc
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Latitudes of visibility
editThe article states
- " It occurs only when the sun is high in the sky, at least 58° above the horizon, and can only occur in the presences of cirrus clouds. It can thus not be observed at locations north of 55°N or south of 55°S, except occasionally at higher latitudes from mountains."
Since in summer the suns elevation is increased by 23.4° , the tilt of the Earths axis, it should be visible as far north/south as latitude 78°. Am I missing something? Lumos3 (talk) 16:08, 10 June 2008 (UTC)
- The calculation already takes into account the Earth axis tilt. By basic geometry (correct me if I'm wrong), the maximum elevation of the sun is roughly (23°+90° – geographical latitude) on the longest day of the year (beginning of summer). 113° minus 55° comes down to 58°. So if this phenomenon requires the elevation of the Sun to be at least 58°, one needs to be closer to the equator than 55° latitude. MHD (talk) 09:22, 13 June 2008 (UTC)
Don't have the time to format a reference for it, but this is also known as a fire rainbow. Is APOD an acceptable source? http://apod.nasa.gov/apod/ap090512.html —Preceding unsigned comment added by John Abbe (talk • contribs) 07:02, 27 February 2010 (UTC)
Further to the above, recent pictures circulating on the internet from Yellowknife (62N) show the Northern Lights and a final picture of a "Fire Rainbow". Pictures of "Fire Rainbows" often look very like pictures I have taken of "Sundogs" (parhelion) which of course are visible to the poles. —Preceding unsigned comment added by Helligon (talk • contribs) 17:13, 31 January 2009 (UTC)
Rare?
editRare? You have gotten to be kidding me....they look exactly like bands of spectral color we get through the sky every few days here in Iowa. Or is there another phenomenon that looks identical that I'm getting mixed up?--AltairIowa (talk) 07:54, 17 May 2009 (UTC)
- you're getting mixed up, bless. — Preceding unsigned comment added by 86.178.234.58 (talk) 18:47, 1 July 2011 (UTC)
Terminology
editThe article alternates between "circumhorizontal arc" and "circumhorizon arc". The latter seems wrong grammatically. Which is it?
Also, I got here via a link for "fire rainbow" from a featured article, but this term is not used here. Is that another accepted name? SelectSplat (talk) 04:48, 29 September 2011 (UTC)
Formatting issue...
editThe new picture is huge. Someone needs to get that sucker sized and sourced right.70.76.99.169 (talk) 02:56, 31 May 2012 (UTC)
rarerity and specialty
editIt has been known that a rainbow cloud is only seen by the human eye when there is a shooting star occuring — Preceding unsigned comment added by 68.179.158.5 (talk) 00:01, 1 August 2012 (UTC)
- Umm, yeah, no. Drabkikker (talk) 09:40, 3 March 2015 (UTC)