MOONBOW

A 'moonbow' (also known as a 'lunar rainbow' or 'white rainbow') is a rainbow that occurs at night. Moonbows are relatively faint, due to the smaller amount of light from the Moon. As with rainbows, they are always in the opposite part of the sky from the moon.
It is difficult to discern colours in a moonbow because the light is usually too faint to excite the cone colour receptors in our eyes. As a result, moonbows often appear to be white.^[1] However, the colours in a moonbow do appear in long exposure photographs.
A coloured circle around the moon is not a moonbow—it is usually a 22° halo produced by refraction through hexagonal ice crystals in cirrus cloud. Coloured rings close to the moon are a corona, a diffraction phenomenon produced by very small water droplets or ice crystals in clouds.
Moonbows are most easily viewed during full moon (when the moon is brightest), just after astronomical twilight in the evening or before astronomical twilight in the morning (when the moon is low, not overhead).

Contents

Famous natural moonbow locations

References

See also

External links

Famous natural moonbow locations

Few places in the world frequently feature this phenomenon. Cumberland Falls Kentucky State Parks, , Bill, Bailey, Glovebox Guidebooks of America, 1995, , near Corbin, Kentucky, U.S.A.; Waimea, Hawaii; and Victoria Falls on the border between Zambia and Zimbabwe are widely known for moonbow occurrence.
Moonbows are commonly reported in Yosemite National Park in the United States as a result of the numerous waterfalls in the area, particularly during spring run-off of melting snow.^[2]

References

1. Lunar Rainbows - When to View and How to Photograph a "Moonbow"
2. Donald W. Olson, et al. "Moonbows over Yosemite" in ''Sky & Telescope'', May 2007.

See also

★ Rainbow

External links

★ Lunar Rainbow photos from Victoria Falls

★ Moonbow picture

★ Moonbow picture made with long exposure

★ Cumberland Falls State Park

★ Moonbow in New Zealand

★ Moonbow predictions - Lower Yosemite Falls - as calculated by Don Olson at Texas State

★ Lower Yosemite Falls Moonbow by Brent Gilstrap, Photographer