STUDI KECERLANGAN LANGIT TERHADAP VISIBILITAS HILAL
First date of Hijriah calendar defined by the thin crescent is first visible after new moon. There are some methods for determining the visibility of the Moon. One common theme is apparent in all the methods. They are all measure of the minimum contrast required to observe the Moon (Hoofman 2002)...
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| Format: | Final Project |
| Language: | Indonesia |
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| Online Access: | https://digilib.itb.ac.id/gdl/view/40942 |
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| Institution: | Institut Teknologi Bandung |
| Language: | Indonesia |
| Summary: | First date of Hijriah calendar defined by the thin crescent is first visible after new
moon. There are some methods for determining the visibility of the Moon. One
common theme is apparent in all the methods. They are all measure of the minimum
contrast required to observe the Moon (Hoofman 2002). The contrast is ratio of two
components: the illuminance of the Moon and the brightness of the sky. The
calculation of sky brightness was using the model derived by Schaefer (1993).
However, the prediction of contrast was using different definitions such as Ilyas
(1984), Schaefer (1993), and Sultan (2006). Result of the calculation show that the
sky brightness proportional to the higher elevation and the altitude of the Moon and
the Sun. However, the sky brightness was inversely proportional to the relative
humidity and separation between sky direction and the Moon and the Sun. The sky
brightness in winter solstice is higher than in summer solstice. The prediction of
contrast using Ilyas and Sultan definition was inversely proportional to the sky
brightness. However, the prediction of contrast using Schaefer definition was
proportional to the sky brightness. |
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