For thousands of years, gazing upward was how astronomers studied the sky above. On a clear night, several planets in our solar system were visible without a telescope. However, as telescopes increased in sophistication, astronomers discovered more planets, confirming the eight in our solar system. As technology continues to progress, though, could we uncover a new one?
Astrophysicists don’t know if there are undiscovered planets in our solar system, but new technologies are enabling researchers to get closer to an answer.
What Is Planet X?
Ancient people and early astronomers long knew about five planets: Jupiter, Mars, Mercury, Saturn, and Venus, though these planets seemed like stars at first. In 1781, a British astronomer identified Uranus as also being a planet and not a star.
In the coming decades, astronomers worked with mathematical equations that suggested there was a planet beyond Uranus. Only in the mid-1800s was a telescope powerful enough to put the planet in scientists’ sights.
