Local Apparent Time (LAT)

To give you some idea of how big the Bandung Sundial is - whose bottom view of its observation deck I posted yesterday - today I'm posting these photos.

This first photo shows the view from the observation deck. As the you can see, the shadow of the gnomon (the sundial's "clock hand") shows that the time is almost 12:00 o'clock - although the term "o'clock" of course would not really be appropriate here as the time is not shown by the clock, but by the sundial.



The time shown by a sundial is called LAT or Local Apparent Time, that is the time as shown by the apparent motion of the sun. Because the earth is not a stationary object in space and because it has an elliptical orbit around the sun, the length of each day is not the same everyday and in different parts of the earth. Therefore, the near noon time shown by this sundial (which is located at Latitude -6.843 and Longitude 107.485) and at the time I took this photo (18 January 2009) will not exactly coincide with nearly 12:00 o'clock noon at other locations that belong to the same time zone as we know it and at a different time of the year.

To get an accurate conversion from LAT to the local clock time, we first need to find the Local Mean Time (LMT), which can be calculated with the following formula:

LMT = LAT - ∆

where ∆ is the value of the equation of time (there is a table for this).

The LMT we get will then need to be fine-tuned against the location's actual longitude.

If you're still confused with all this, then the most important thing is - I think - the basic principles of how it works.



By the way, this second photograph is the bridge that surrounds the sundial. The strips you see here are the minute markers.

Skywatch: The Sundial Observation Deck

This is the bottom view of the observation deck and tip of the hand (called gnomon) of the Sundial at Kota Baru Parahyangan in the West of Bandung. For those of you who did not regularly follow my blog, I have previously posted a photo and story about this sundial here.

For a more comprehensive information about sundials, you may want to read this wikipedia article.

This post is BANDUNG DAILY PHOTO's participation in the weekly Skywatch Friday meme. Please check out the link to see other participants' photos.

Merak Hijau (Green Peacock)

This green peacock (Pavo Muticus) is one of Bandung Zoo's aviary collections. Green peacock is one of the three species of peacocks. The other two species are the blue or Indian peacock (Pavo Cristatus) and the Congolese African peacock (Afropavo Congensis).

The green peacock is native to and can still be found wild on the Indonesia's island of Java (I've seen it myself once in Meru Betiri National Park in the eastern tip of the Island). It can also be found in Indochina, particularly Burma (Myanmar). Its blue sibling, meanwhile, is found mostly on the Asian subcontinent (India, Pakistan, and Bangladesh).

Although quite a misnomer, the name "peacock" is generally used to refer to both male and female individuals of this bird. Technically the name "peacock" only applies to the male bird. The female bird is called "peahen", and together they are called "peafowl".

The famous iridescent tail of this bird belongs to the the male species (the peacock) and is used to attract the female (the peahen) in courtship and mating rituals.

Peafowl is omnivorous ground feeder and its diets mainly consist of insects, small animals, and plants.

Peafowl is an important bird for the Javanese and Sundanese (the people and language of West Java). Its beauty has long inspired several forms of art performances. One of them is Tari Merak (The Peacock Dance) whose photos and story I posted earlier here.