RE: Where is Azimuth = 0?

David Irwin (
Tue, 22 Apr 1997 11:06:54 +-100

Some years ago I was managing a remote sensing tracking station, =
receiving data from Landsat, SPOT and NOAA satellites.  We had problems =
processing the SPOT data, and found that SPOT used an inverted compass =
card - east was 270, west was 090.

North was 0 though!


Sent: 	20 April 1997 19:13
Subject: 	Re: Where is Azimuth =3D 0?

Bram Dorreman wrote:

>When an observer describes his(or her) observation often it is
>described by specifying Azimuth and Altitude. I noticed that
>many people use Azimuth =3D 0 being North. I changed several
>times in using Azimuth =3D 0 being either North or South
>following a recomendation of people from which I expect they
>should know.

Here's my two cents, since everyone else has chipped in :)

I have a surveying textbook that defines azimuth as "a horizontal angle
measured clockwise from the local meridian using either true north or =
as 0 degrees."  It goes on to say that measuring from the north is the
norm, but some geodetic work uses south as zero.

Bate, Mueller and White's "Fundamentals of Astrodynamics" and Escobal's
"Methods of Orbit Determination" both use the North =3D 0 convention.

Jim Varney     Sacramento, CA