Tuesday, June 29, 2021
Astrometeorology 5, Qibla
I'm still not in the mood for graphics, but sometimes you have to MAKE something to break out of dull moods. So I'll continue with a review of previous segment.
= = = = = START REPRINT:
This is the tool that archeologists call Instrument 3. It's a simple sighter for both azimuth and altitude. Polistra is trying to realign with the beacons of the universe.
The sighting bar with two pinholes or gunsights is the alidade. It's the key element of these instruments and astrolabes.
= = = = = END REPRINT.
This instrument to sight on both azimuth and altitude spawned more specialized instruments for each direction. Previous item covered the altitude part, the astrolabe.
Today I'll hit the azimuth part, the qibla finder, which has a special purpose in Islam.
Qibla is simply the direction from your location to Mecca. It has been precalculated and mapped for all locations, using Great Circle methods. The qibla finder uses a map based on the precalculated directions, or just lists cities around a circle.
Here Polistra is holding a more deluxe round qibla finder, in parallel with the azimuth of the big instrument.
And here she's holding a little pocket-sized square qibla finder, which happens to look a lot like a certain modern device. And in fact modern Muslims typically use an app that turns the screen of the modern device into a qibla finder similar to this one.
Closeup look of the square finder. All proper finders have two elements, a magnetic compass and an alidade. The alidade can be used two ways. First line the top of the finder with north, like a regular compass. If you don't know the qibla direction for your location, you can sight to the sun at sunset and use a table to determine the qibla direction. This is obsolete, since all locations are known. The more practical way is just to turn the alidade so its pointer hits the name of your location on the map, and then face from the pointer inward toward Mecca. The original of this model appeared to have some city names, so I just showed a compass grid.
The round finder is more typical, with a real map. I've got the pointer aimed at France.
This is poorly written, but will have to do for now. Sorry!
The sighting bar with two pinholes or gunsights is the alidade. It's the key element of these instruments and astrolabes.
= = = = = END REPRINT.
This instrument to sight on both azimuth and altitude spawned more specialized instruments for each direction. Previous item covered the altitude part, the astrolabe.
Today I'll hit the azimuth part, the qibla finder, which has a special purpose in Islam.
Qibla is simply the direction from your location to Mecca. It has been precalculated and mapped for all locations, using Great Circle methods. The qibla finder uses a map based on the precalculated directions, or just lists cities around a circle.
Here Polistra is holding a more deluxe round qibla finder, in parallel with the azimuth of the big instrument.
And here she's holding a little pocket-sized square qibla finder, which happens to look a lot like a certain modern device. And in fact modern Muslims typically use an app that turns the screen of the modern device into a qibla finder similar to this one.
Closeup look of the square finder. All proper finders have two elements, a magnetic compass and an alidade. The alidade can be used two ways. First line the top of the finder with north, like a regular compass. If you don't know the qibla direction for your location, you can sight to the sun at sunset and use a table to determine the qibla direction. This is obsolete, since all locations are known. The more practical way is just to turn the alidade so its pointer hits the name of your location on the map, and then face from the pointer inward toward Mecca. The original of this model appeared to have some city names, so I just showed a compass grid.
The round finder is more typical, with a real map. I've got the pointer aimed at France.
This is poorly written, but will have to do for now. Sorry!
Labels: Equipoise, Natural law = Sharia law
¶ 3:16 PM
