Coloured Moon

[ultramol]

I have just been observing the moon and after about 10 minutes I noticed blue, yellow and a greeny colour running around the outside of it. I have never noticed this before. Has anyone any ideas what could cause this . My Bins are inpro 15x70 fully coated. The first 10 minutes of observing were fine ?

[Paul M]

I've been looking at the Moon tonight also. First thing I noticed was the dreadful seeing. "Seeing" specifically refers to the stability of the atmosphere.

Although the air was very clear it's also very unstable. Currents and motion through the full depth of the atmosphere have random small scale refractive effects on light passing through. This can also cause colours to appear too.

A fine example can be seen while observing bright stars during bad seeing. The brighter the object the worse the effect seems to be. Sirius can dance and shimmer with all kinds of colours being displayed. Very pretty but no good for observing with optical instruments!

[ultramol]

Thanks for that Paul. I thought something had happened to my bins !