| International Dark-Sky Association (IDA) | Southern California Light Pollution Map |
| (The) Greek Alphabet | Greek Alphabet Table |
| Limiting Magnitude of Your Telescope | Hot to Estimate a Comet's Brightness | (The) Pickering Seeing Scale |
| Hale Telescope Web Cam |
| ATM Page | ATM Programs |
| Astromart | Astronomical Telescope and Optics Formulas | Riverside Telescope Makers Conference (RTMC) |