Meaning of "azimuth" in this context.

[ChrisGreaves]

Suppose, just suppose, that for giggles I was to erect a signpost for all the truly important places on Earth. I might use this site: https://planetcalc.com/7042/
I key in the lat/long for Bonavista and then the lat/long for some other place, and get these results:

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Bonavista Azores 
Azimuth     122°4'22"
Distance in km     2160.938
Distance in nautical miles     1166.813
Compass point     ESE / East-southeast / Levante-Scirocco
Compass point degrees     112°30'0"
Compass point decimal degrees     112.5

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Bonavista Toronto
Azimuth     254°42'41"
Distance in km     2100.286
Distance in nautical miles     1134.064
Compass point     WSW / West-southwest / Ponente-Libeccio
Compass point degrees     247°30'0"
Compass point decimal degrees     247.5

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Bonavista Telegraph Creek
Azimuth     268°32'43"
Distance in km     4068.657
Distance in nautical miles     2196.899
Compass point     W / West / Ponente (Zephyrus)
Compass point degrees     270°0'0"
Compass point decimal degrees     270

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Bonavista Paris
Azimuth     89°39'22"
Distance in km     4078.202
Distance in nautical miles     2202.053
Compass point     E / East / Levante (Oriente)
Compass point degrees     90°0'0"
Compass point decimal degrees     90

I suspect that "azimuth" here refers to a 360-degree position around a circle where 90º is the equivalent of three o'clock on a clock face, and hence means that the point is horizontally to my right. Then Toronto and telegraph Creek would be (almost) horizontally to my left.
Does that sound right?
I looked for Perth Western Australia and got "Azimuth 117°47'51" which is not The Antiopde(s), but is getting there.

My signpost could indicate not only the N/E/S/W direction, but also the direction to drill a hole through the earth.
Thanks
Chris

[HansV]

See Azimuth in cartography.
It is indeed the clockwise angle relative to the north (i.e. north = 0°, east = 90°, south = 180° and west = 270°).

[ChrisGreaves]

See Azimuth in cartography.
It is indeed the clockwise angle relative to the north (i.e. north = 0°, east = 90°, south = 180° and west = 270°).

Thank you for the confirmation, Hans.
"The Arabic word entered late medieval Latin in an astronomy context" This text was good, as I had begun to suspect already that my confusion arose from the use of (and my exposure to) the word azimuth in the context of astronomy and star-gazing.

If I do build the thing, I will have to use double- or triple-bolting, otherwise my neighbours will think that the signpost is just one more example of my poor carpentry skills.

FWIW I found https://www.antipodesmap.com/ to locate the antipode of Bonavista.
Cheers
Chris

[Graeme]

My signpost could indicate not only the N/E/S/W direction, but also the direction to drill a hole through the earth.

Interesting project Chris.

Whilst star gazing, the coordinates of a celestial object can be indicated by Azimuth and also Altitude. Azimuth as described and Altitude measured up from 0° at the horizon to 90° at the zenith. Perhaps you could use minus altitude as the signpost drill down angle measurement?

Regards

Graeme

[Leif]

...Altitude measured up from 0° at the horizon...

Genuine question - what defines the horizon? 90°to the perpendicular?

[ChrisGreaves]

Genuine question - what defines the horizon? 90°to the perpendicular?

In school we were taught that "horizon" should be used only at sea, but on land "skyline" should be used.
For what, i do not remember.
Steven Pinker (I think) pointed out that The Horizon was one of the few genuine straight lines in nature.
Cheers
Chris

[Leif]

...but on land "skyline" should be used.

Like this?

x.jpg

    
    

Steven Pinker (I think) pointed out that The Horizon was one of the few genuine straight lines in nature.

Is that the Steve Pinker of the Flat Earth Society?

[Graeme]

...Altitude measured up from 0° at the horizon...

Genuine question - what defines the horizon? 90°to the perpendicular?

90° from the Zenith would be good! Perhaps sea level is assumed? Dunno really, but you can't see much through a telescope at that altitude anyway!

Azimuth and Altitude are in the eye of the beholder, since the coordinates to a location would change as one moves across the surface of the Earth. In a similar way the coordinates of celestial objects constantly change as the Earth rotates and orbits the Sun. Right Ascension and Declination are fixed coordinates with respect to the background stars.

Sorry I'm rambling!

Regards

Graeme

[DaveA]

Since I was in a artillery unit in the US Army and for elevation (altitude) a "level" with a air bubble was used, So Zero would be the horizon and 90 degrees would be straight up from there.

For more information have a read at https://en.wikipedia.org/wiki/Gun_laying

[ChrisGreaves]

... Perhaps you could use minus altitude as the signpost drill down angle measurement?

Hi Graeme.
It will be a kit (which I can offer to members of Eileen's Lounge.
The kit will include the template for a single signpost (so you can cut as many location-signs as you want from scrap wood), and two protractors (one for compass point and one for azimuth), and a clip designed to fit the sign to the vertical pole. Also perhaps a stencil kit with 26 letters and ten decimal digits. Km only, so not available to residents of the USA
The vertical pole will slip into a twelve-inch piece of 3/4" galvanized iron pipe hammered into the ground, so that as a signpost fills up (grows too cluttered), I can start another one.

This could be a tourist attraction, along the lines of "drop off the name of your home-town and in 24 hours we will add your signpost to our pole"

With a bit of luck each "customer" will take two swipes at my book bin and help me gain more space in the guest bedroom.

Cheers
Chris

[ChrisGreaves]

Like this? x.jpg

No, If I knew where it was I would refer to this post which suggests a solution for your zig-zag set of lines.

Is that the Steve Pinker of the Flat Earth Society?

I doubt it! It is the Steven Pinker of, I think, "How The Mind Works", but I am not scheduled to re-read that until November, so I can't quote a page number.
Otherwise it might be Richard Dawkins. (ref "November" above)
Cheers
Chris

[ChrisGreaves]

... as one moves across the surface of the Earth. ... Sorry I'm rambling!

Well, of course! How else can a biped move across the surface of the earth?
Cheers
Chris

[ChrisGreaves]

Since I was in a artillery unit in the US Army and for elevation (altitude) a "level" with a air bubble was used, So Zero would be the horizon and 90 degrees would be straight up from there. For more information have a read at https://en.wikipedia.org/wiki/Gun_laying

Hi Dave.
page 32 of my copy of "The First Cuckoo" reprints a letter from Dr. A. Conan Doyle to The Times February 22 1900. He attacks the war department board responsible for "inventions", using his example of a suggestion for "dropping, or high-angle rifle fire".
A report on his letter to The Times can be found in The Westminster Gazette".
I cannot readily find an online reference to his letter to The Times, but could email photographs of the three pages in my book to any lounge member interested in reading about his idea.

To the best of my knowledge Dr Conan Doyle never wrote about Bonavista.

Cheers
Chris

[jolivanes]

Re: "but also the direction to drill a hole through the earth."
When they drill a hole they normally start by going straight down but they call this zero degrees (not 90) and thus does not have a direction (azimuth).