Rainbow Isle

The Island of Hawai`i has three nicknames that I'm aware of: "The Big Island", "Orchid Isle" and "Rainbow Isle". It's certainly been living up to that last name during the last 24 hours or so. Yesterday evening, just before sunset, I caught the rainbow pictured in "Sunset rainbow" and at dawn today there were at least four separate rainbows that appeared in the north-western sky. Most were partial rainbows and not easy to photograph from my location, but I did catch the one above. Incidentally, what is the collective noun for a group of rainbows?

My main interest in astronomy is spectroscopy; splitting up the light from asteroids, comets, planets, stars and galaxies into its component wavelengths in order to identify and understand the physical and chemical processes occurring in space. Spectroscopy does, as you might imagine, become quite a technical and complicated technique in modern science and it can be easy to forget that the physics behind spectrographs is already employed by nature to produce some of the most wonderful phenomena one witnesses on our planet. Physics can be beautiful!

The shot below is another view of yesterday's sunset rainbow. As Hilary mentioned in her very kind comment on my post, the colours were vivid. That's often the case with rainbows here, I think it's because we have a lot of rain and very bright sunlight; there's little air pollution to dilute the sun's light (unless the winds are blowing the VOG this way from Kilauea). Yesterday's rainbow was made even more vivid by the dark and ominous-looking clouds just off the coast. What caught my attention with this one was that even though the rainbow was bright and fairly well defined, it appeared to cut-off just a little way above the ocean. It reminded me of Orson Wells' "The War of the Worlds" and the movie "Independence Day" - it was an alien death-ray beamed from a spaceship hiding in the clouds!