||The sun slips slowly downwards to a clear
ocean horizon. Ever reddening as it sinks, soon only a thin sliver
of the once hot disk is left. Then, as that too shrinks and lessens,
it shines forth for just a second in a most vivid emerald green. Then
it is gone, only the dark ocean remains. That is the green flash of
Flashes like that do occur. A clear atmosphere produces the best ones
but it is not absolutely essential. Sometimes the flash is more yellow,
very rarely it is even blue. If you are energetic,
observe on a hill or dune and run up after the flash has occurred
- you could see another one. There are sunrise flashes too if you
are alert for the very place and moment that the sun will appear.
There are other types of flash. Some do not need an ocean horizon.
The next few pages describe them and the subtle atmospheric conditions
that produce their colour and brilliance. There also some clues as
to which sunsets will produce them. ↓
Take care of your eyes. Never stare at the sun
and never look at it through binoculars, a telescope or the optical
viewfinder of an SLR camera - your eyesight could be permanently damaged. ↓
This section owes much to green flash expert
Andrew T Young and his site
should be consulted for a definitive account. Thanks also to all
for generously giving permission to use their fine images.