Help Centre

This is the place to come when you get stuck, or can't figure out how to do something.

Navigation and usage help | Technical help

Navigation and Usage

How to use this site

Please read the introduction, before taking the Main Tour. Movies have a simple caption which changes as it progresses. The solar system movies also have a voice commentary.

Many movies may also be viewed with explanations. In this view, detailed information about each scene is found by clicking on "Tell me More" under the caption.

In depth discussions are found in the Learning Centre, linked to in the Navigation Bar. Many Learning Centre topics are based on movies. It also contains a glossary, which can help you understand technical words, a bibliography, and a list of relevant web sites, which you can use to find more information.


This site is organised into a Main Tour and a Learning Centre Tour. To take these tours follow the Continue Tour link in the Navigation Bar. The Main Tour highlights visual effects that occur in special relativity. The Learning Centre explores these in detail, as well as more traditional topics in relativity such as time dilation.

The drop down menu in the Navigation Bar links to major pages. The site map lists all the pages on the site. It includes a menu of all of the movies.

The browser "Back" button may not work as expected. Instead, use the Navigation bar, or site map.

Movie windows

There are two types of movie window: Big movies with a brief caption, and "explained" windows with a half size movie plus additional information. This information may link to short definitions.

They also have a "Tell me more" link under the caption, which gives detailed explanations: usually more than can be read while the movie is playing. You may click the movie to pause it, and double click to restart it.

The explanation has links to short definitions of key concepts. These link on to full explanations, which open in another window.

Technical Help

Updated information is available on the web (web connection needed).

Movies won't load

Quicktime must be installed on your computer for the movies to work. You can obtain it from the QuickTime download site. If you are running the site from a CD, installers should be on it.

If the movies do not load, or you get a broken movie icon, there are several things you can do.

  • Quit and restart your browser.
  • Check you have the latest version of Quicktime. This site requires at least version 6.5 of QuickTime. See paragraph above to obtain it.
  • Try a different browser.
  • Check the online site for further help.
  • Contact us.

Screen resolution

This site is designed to display in a browser window of 900 wide x 750 high. This requires a screen resolution of at least 1024x768.

Browser compatibility

If you are having problems, check the list of browsers we have tested this site on, and the problems we have experienced.

On Windows systems we recommend the Firefox browser, and on Macintosh systems Safari. If you hear annoying clicking sounds with Windows Explorer, you can find out how to turn them off. On Macintoshes, the site does not work well with Internet Explorer.

Movies won't play smoothly

Movies will only play smoothly if your computer system and browser are fast enough. However, they should play acceptably on recent systems.

Movies may load faster if you copy the entire site onto your hard disk.

You may get smoother movie playing by accessing the movies directly in the movies folder. However you will then not have access to the text information windows.

Contact us

We like to hear from you. Let us know what you liked about the site, and about any problems you may have.