Rainbows

[BoroughGal]

Can anyone tell me what determines the shape of the arc of rainbows?  Sometimes they are very wide and long, sometimes high and thin.  I need this in laymans terms (I've tried looking it up on the internet before and got baffled!). Is it, for example, the time of day, or the time of year, (ie the position of the sun in the sky being reflected in different ways??).

Thanks...

[Gnu]

It is possible to see a completely circular rainbow if you are in a plane.  The 'centre' of the rainbow will be directly opposite the sun's position, so a low sun will result in a rainbow that is almost semi-circular.  As for the width of the rainbow, that probably depends on the distance of the rain from you - the further away the rain is, the larger, but thinner the rainbow.

[BoroughGal]

Thank you very much for that...

[BoroughGal]

I'm not sure whether or not this thread will be read after all this length of time - but I just wanted to say to Gnu that - on my first trip abroad since I posted the question above - I saw a circular rainbow!!!!!  I first saw a shadow of the plane against the clouds, then saw a faint rainbow round where the sun was, just outside the shadow of the plane!  Wow!  Thanks for telling me about that.

I don't know how good this photo is, but check it out:

http://img.photobucket.com/albums/v601/g1rrrrly/DSC01052 .jpg

[BoroughGal]

I'll try the link again as it doesn't appear to work on the one above - but apologies if not.

[BoroughGal]

http://img.photobucket.com/albums/v601/g1rrrrly/DSC01052 .jpg