Metaclock

The nice thing a timescales is that there are so many to choose from: solar, atomic, sidereal, local, apparent, dynamical. Here is a javascript clock showing some of the more well-known. The latitude and longitude are modifiable and affect the values of the local times and UT0. Earth rotation parameters use the estimation formulas from a recent IERS Bulletin A.

The clock has several manifestations, controlled by the style sheet used:

Plain Clock

Standard Clock

Milspec Clock

Steampunk Clock

This was written partly as an exercise in javascript and CSS and I would be happy to hear of any problems or bugs.

Values are generally displayed to a ludicrous precision, the accuracy may be rather less. In particular, values for Sun Right Ascension and Declination may be 10-20 arcsecs out.

Links

For another clock see: An Astronomical Clock

Other web pages I found useful:

http://www.gb.nrao.edu/~rfisher/Ephemerides/times.html

An excellent introduction to timescales.

ftp://maia.usno.navy.mil/ser7/ser7.dat

IERS Bulletin A. The very latest data on the rotation of the earth and the relation between UT0, UT1 and UT2.

http://aa.usno.navy.mil/faq/docs/GAST.html

The relation between apparent and mean sidereal time.

http://www.xylem.f2s.com/kepler/sidereal.htm

More on sidereal time and the equation of the equinoxes.