On February 18, 1930, a significant event in the history of science took place when Clyde Tombaugh, a young astronomer at the Lowell Observatory in Flagstaff, Arizona, discovered the dwarf planet Pluto.
Tombaugh had been tasked with the job of systematically searching for a hypothetical "Planet X" that was believed to be causing perturbations in the orbits of Uranus and Neptune. He used a blink comparator, a device that rapidly switched between two photographs of the same area of the sky taken at different times, to look for any objects that had moved position, indicating that they were closer to Earth than the background stars.
On that fateful day, after months of diligent work, Tombaugh noticed a faint speck of light that seemed to jump back and forth between the two photographs. He had found Pluto, located at an average distance of 3.7 billion miles (5.9 billion kilometers) from the Sun. At the time, Pluto was considered to be the ninth planet in our solar system.
The discovery of Pluto was a momentous occasion, as it was the first planet to be discovered in modern times and the first to be found by an American. The news of the discovery spread quickly, and Pluto became a household name.
However, as more objects were discovered in the outer reaches of the solar system, astronomers began to question whether Pluto truly deserved to be classified as a planet. In 2006, the International Astronomical Union (IAU) created a new definition for planets and reclassified Pluto as a "dwarf planet."
Despite its reclassification, the discovery of Pluto remains a significant milestone in the history of astronomy and planetary science. It paved the way for the discovery of numerous other objects in the Kuiper Belt, a region of the outer solar system beyond the orbit of Neptune, and has helped us to better understand the complex nature of our cosmic neighborhood.
This content was created in partnership and with the help of Artificial Intelligence AI
