Thursday, March 08, 2007

Reflected rainbows near Spitsbergen

On 22nd August 2006 between 20.35-20.50 hrs, while cruising on the Isfjord near Spitsbergen, Nicola Boll watched these wonderful reflected rainbows. The lower bow is an ordinary primary bow. Intersecting it and curving upwards above it is a 'reflection bow'. The bow is formed by sunlight reflected off the smooth waters of the fjord. The upward going reflected rays are, in effect, from a 'virtual sun' the same distance below the horizon as the real sun was above it. Since rainbows are always centred opposite the light source, the centre of the reflected bow is up in the sky and the bow correspondingly high. In the picture enhanced by unsharp masking a reflection bow is also visible curving upwards above and to the right of the secondary rainbow.

Thursday, March 01, 2007

Rainbow season started early with a twinned primary

While homeward bound from work a small rainshower started to pour in bright sunlight and I looked the the north and got a flat looking rainbow. I was ride-sharing when this happened and we pulled over and I got some photos and the bow looked unusual. Upon downloading the photos I applied unsharp mask and noticed the primary was twinned primary bow. This is the first rainbow for me this year. I would of expected to see one in the spring not February!