Sunrise and Sunsets

Issue Date: 10 January 2001







Sunrise and Sunsets Stamp Issue

Our first issue for 2001 depicts beautiful local sunrises and sunsets reproduced from negatives and transparencies by local Photographer and author I Strange.

Colour in the form of pigment does not exist in the atmosphere. Instead we see in the sky results from the scattering, refraction and diffraction of sunlight by particles in the atmosphere which may be air molecules, ice, water or dust particles.

Sunlight travels through the solar system in straight invisible waves. This "white" light is a mixture of all the colours which make up the visible portion of the radiation spectrum, for example the colours one sees in a rainbow i.e. red, orange, yellow, green, blue, indigo and violet. Each of these colours we see travels at different wavelengths, the reds have the longest wavelengths while the indigo and violet have the shortest.

When sunlight hits the atmosphere, the light waves are scatered in different directions by the air molecules and dust particles. The shorter violet and blue waves are scattered more than the longer orange or red waves. When the sun is high the violet, blue and green waves with small amounts of the others are scattered more effectively producing a blue sky. Water vapour and dust of commonly what we term "pollution" can affect the intensity of this blue.

With lower levels of pollution in the Falkland Islands, skies often appear a more intense blue. The 43p value illustrates a summer sunrise in the SW if the Islands with a predomenance of blue.

As the sun rises or sets, its light travels a longer path through the atmosphere. More of the colours at the red end of the spectrum are scattered and the sky turns from yellow to orange to red. The scattering by air alone merely makes the setting sun yellow as shown in the 37p value of a scene over Stanley during winter. If there is even nuclei on which water vapour is condensed the rising sun can be orange, as illustrated in the 10p value of a sunrise at New Island during the autumn.

Volcanic dust has a significant effect on red sunsets. The addition of such dust to the atmosphere increases the number of particles and hence the scattering of colours. This means that the colours at the red end of the spectrum are more effectively dispersed across the sky. Often known as volcanic twilights, such sunsets are typically an intense red to purple. The dramatic sunset over Stanley shown in the 20p value occured during the eruption of Mount Hudson. However, similar sunsets occured in the last days of the 1982 conflict. With the lower atmosphere polluted from the smoke of cordite and fires, sunsets were not uncommonly a deep red to purple.

The First Day Cover design illustrates a typical Falklands sunset with the phenomenon of a "sun pillar" due to the reflection of sunlight from ice crystals. Photo, Georgina Strange.



Technical Details

Designer: I Strange
Printer: The House Of Questa
Process: Lithography
Stamp Size: 27.94 x 44.45
Pane: 50 (2 x 25)
Perforation Gauge: 14 per 2cms
Watermark: Crown Agents
Release Date: 10.01.01
Values: 10p, 20p, 37p, 43p.





Copyright: FI Philatelic Bureau Created and Maintained by: Cyberpoint Limited