# ODDS AND ENDS:

**Some miscellaneous programs useful in the course of archaeoastronomical field survey.**

Created by **Clive Ruggles***

**Terminology**. *Elevation* means the height of a location above sea level.
*Altitude* means the vertical angle between a viewed point and the horizontal plane
through the observer. Elevation, then, is a distance; altitude is an angle.
Cf. *Astronomy in Prehistoric Britain and Ireland*, p. ix.

## GRIDLA

Converts a Transverse Mercator Grid easting and northing to latitude and longitude.
The TM Grids currently catered for are the British and Irish National Grids, the Greek EGSA87
Grid, and UTM. Note that UTM northings in the northern hemisphere must include the initial "1"
(i.e. the equator has a northing of 10000000). Convergence, local scale factor and bending
are also calculated. Click here to download the program.

## LAGRID

Converts a latitude and longitude to a Transverse Mercator Grid easting and northing.
Again, the TM Grids currently catered for are the British and Irish National Grids,
the Greek EGSA87 Grid, and UTM. Convergence, local scale factor and bending
are also calculated. Click here to download the program.

## DECTOAZ

Given a declination, latitude of the site, and altitude of the horizon, this program
calculates the corresponding azimuth on the eastern and western horizon.
Click here to download the program.

Click here to return to "Archaeoastronomy programs".

Author: Clive Ruggles

* Some of these programs are adapted from a set of programs originally written between
1975 and 1984 by John Cooke, Roger Few, Guy Morgan, and Clive Ruggles.