从portaltotheuniverse.org链接出的网站列表
| No. | 链出域名 | 关键词 |
|---|---|---|
| 1. | astronomy2009.org | |
| 2. | apple.com | |
| 3. | nasa.gov | more |
| 4. | eso.org | |
| 5. | calculatorcat.com | about the moon |
| 6. | exoplanet.eu | more |
| 7. | noaa.gov | |
| 8. | heavens-above.com | |
| 9. | cleardarksky.com | |
| 10. | harvard.edu | more |
| 11. | spacetelescope.org | |
| 12. | qsl.net | |
| 13. | spaceweather.com | more |
| 14. | unesco.org | |
| 15. | iau.org | |
| 16. | esa.int | |