Positional Astronomy

In February 1998, I gave a short series of lectures on Positional Astronomy
for second-year undergraduate students at the University of St.Andrews, Scotland.

These pages were created in 1998 to assist the students.
I now maintain them, in a revised and expanded form,
partly to assist the current generation of students at St.Andrews,
and partly as a service to the world-wide community.

You are welcome to link to this site from your own pages.
But please do not reproduce any of this material without acknowledgement.

Notes:

(1) Many of the equations use Greek letters as symbols. 
If your browser does not distinguish between "a,b" and "α, β" (the Greek letters "alpha, beta") then I am afraid you will not be able to make much sense of the equations.

(2) These pages use "classical" definitions and terminology:
that is, those used previous to the International Astronomical Union's 2000 resolutions.
(For more information about this, see USNO Circular No.179.)

• Introduction

• The Terrestrial Sphere

• Spherical Trigonometry

• Coordinate Systems: the horizontal or "alt-az" system

• Coordinate systems: the first equatorial or "HA-dec." system

• Coordinate systems: the second equatorial or "RA-dec." system

• Sidereal Time

• Conversion between horizontal and equatorial systems

• Galactic coordinates

• Ecliptic coordinates

• Equatorial and ecliptic coordinates

• The Sun's motion, and its effect on time-keeping

• The Moon

• Refraction

• Sunrise, sunset and twilight

• Geocentric or diurnal parallax

• Annual parallax

• Aberration

• Precession

• Calendars

• Exercise

Comments, complaints or queries? Please e-mail me:
the address consists of my two initials, followed by "@st-and.ac.uk".

Fiona Vincent
University of St.Andrews

Originally created March 1998.
Revised and updated November 2003.