Celestia Forums

At the moment I'm doing a Physics project, and part of it requires data on the positions (ideally in x, y, z co-ords) of planets/the sun at given points in time.

Does anyone know where I could find such data? I've trawled the NASA site, but so far to no avail.

I'm not quite sure what you mean by "the NASA site". There's not just one, there are thousandss of them. The place to get xyz coordinates is JPL's Horizons ephemeris system. http://ssd.jpl.nasa.gov/horizons.html

Its telnet and e'mail interfaces have more features than the Web interface, though. Read the Web page for details.

I hope this helps a little.