Log in

View Full Version here: : Moon Bow


middy
29-03-2010, 10:57 PM
Is that the right expression for a large bright ring around the moon?

I just walked outside to check the cloud situation and saw a beautiful moon bow around the moon. It wouldn't fit into the field of view of the trusty Kodak point and shoot.

This is two 24 second exposures stitched together with Hugin to get the full ring.

middy
29-03-2010, 11:51 PM
Actually I just did some searching and moonbow is not the correct expression. Moonbows, like rainbows, occur in the opposite side of the sky. This is actually a moon halo which is a 22 degree circle around the moon caused by the moonlight being refracted through ice crystals high in the atmosphere.

I confirmed the angle to be 22 degrees in the picture by using a star chart program to measure the angle from the moon to the rightmost star in Corvus (visible as the four stars just inside the ring on the right hand side) at the time the image was taken. :thumbsup:

Dennis
30-03-2010, 07:24 AM
Nice capture Andrew – looks quite stunning. That bright street light at lower left looks like quite a nuisance!

Cheers

Dennis

h0ughy
30-03-2010, 07:59 AM
well done mate, your stitching is pretty good to

middy
30-03-2010, 09:46 AM
Thanks Dennis. It was actually a lot more prominent in real life though, and yes that is one of two street lights I have shining down into my back garden. :sadeyes:

Houghy, that was the first time I had tried Hugin and I thought it did a pretty good job too. I will have to try it on a daytime panorama. I found reference to it here on IceInSpace when I searched for 'photo stitch'. I saw the words "open source" i.e. free and thought "That's the program for me!" :D

mswhin63
30-03-2010, 08:02 PM
Great shot, I tried to get an image of the same thing here in Perth few days ago but failed. Nevermind but it truly represent what I saw here as well.