Planet X Summary

Everything you need to understand or teach Planet X.

  • 2 Encyclopedia Articles

Study Pack

The Planet X Study Pack contains:

Encyclopedia Articles (2)

491 words, approx. 2 pages
Planet X Ever since the discovery of the ninth planet, Pluto, astronomers have speculated about whether a still more distant, tenth planet may exist. This thinking was initially based on two lines of ... Read more
455 words, approx. 2 pages
Planet X Is there another planet beyond Pluto? Prior to 1781 that question could have been asked in regard to Saturn. In that year, Sir William Herschel discovered Uranus, after detecting what he beli... Read more