Lunar Primary & Secondary Bows

Peter O'Toole's first moonbow images from County Donegal, Ireland.  6th October '11 with the moon 11.2 days old - two days past first quarter.    ©Peter O'Toole, shown with permission

The outer secondary rainbow is faintly visible with the darker sky of Alexanders dark band between the two bows.

"Here are my first Moonbow shots! I took them in Glenveagh Park, Donegal where there are excellent dark skies and a lot of showers feeding down from the hills across the boglands. It wasn't long before I spotted my first moonbow a truly amazing sight, just couldn't believe my eyes to what i was seeing  - ghostly phantoms of white 180 degree arcs of refracted light, The colours were invisible to my eyes but evident in the photos. I have also attached monochrome versions [lowest image] to show what moonbow really look like to the naked vision although there have been reports of bow colours being seen.  Also visible in some of the shots are very faint secondary bows.
Taken 23.30- 00.00hrs BST on 6th October with Pentax K-x, 18-55 zoom Lens kit set at 18mm, F/3.5, ISO1600 for 10 secs."


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To best catch a moonbow:

(1) find a locale with frequent short showers and clouds interspersed with clear skies.    Ireland, the Western Highlands of Scotland, Hawaii and Patagonia are good but not exclusive locations.   

(2) Find dark skies away from city light pollution.   

(3) The moon must be less than 40 degrees high.  

(4) A full moon is good but it is not essential (see the moonbow challenge).  

(5) Twilight should be over but they can be spotted during late twilight.   

(6) There must be rain opposite the moon and the raindrops must be moonlit.  

(7) Be patient and prepared to get wet!