Circle Around The Moon

Last night (around 11pm - 31/oct/2009) I was surprised to see the moon looking like this...



there was a big circle around the moon! Thanx to my student, Amirul Bakhri for the above photos.

Well... after asking mr. google... here is what I've found from my little research on the net...

It's a phenomenon called a corona (or a halo). Light reflecting through the moisture of thin clouds produces the ring(s) around the moon.

from mr. wiki..

A halo (ἅλως; also known as a nimbus, icebow or Gloriole) is an optical phenomenon produced by ice crystals creating colored or white arcs and spots in the sky. Many are near the sun or moon but others are elsewhere and even in the opposite part of the sky. They can also form around artificial lights in very cold weather when ice crystals called diamond dust are floating in the nearby air.

There are many types of ice halos. They are produced by the ice crystals in cirrus clouds high (5–10 km, or 3–6 miles) in the upper troposphere. The particular shape and orientation of the crystals is responsible for the type of halo observed. Light is reflected and refracted by the ice crystals and may split up into colors because of dispersion. The crystals behave like prisms and mirrors, refracting and reflecting sunlight between their faces, sending shafts of light in particular directions.

Atmospheric phenomena such as halos were used as part of weather lore as an empirical means of weather forecasting before meteorology was developed.

Other common optical phenomena involving water droplets rather than ice crystals include the glory and the rainbow.

photos from the net...