Is there a hidden planet in our solar system? Astronomers say the moment of truth is near

# The Ongoing Debate Over Planet Nine

For centuries, our solar system was believed to have nine planets. However, with the reclassification of Pluto as a dwarf planet, that number was reduced to eight. This change was precipitated by the discovery of Eris in the Kuiper Belt, which prompted a reevaluation of what constitutes a planet. 

The Kuiper Belt, a collection of icy objects beyond Neptune, is believed to stretch much farther than Earth's distance from the sun, encompassing countless small bodies like Pluto and Eris. These objects, while significant, do not clear their orbits and thus are not classified as planets under current guidelines.

Scientists now suggest that the Kuiper Belt might hold the key to finding a new ninth planet, which could significantly alter our understanding of the solar system. This hypothetical planet is thought to have a substantial mass and a long orbital period. Its existence could explain unusual gravitational influences observed in the region.

The debate over Planet Nine is heated, with various camps proposing different theories. Some suggest the hidden planet could be a super-Earth with mass several times that of our own planet, while others propose smaller masses or even alternative explanations such as a primordial black hole.

Efforts to find this elusive planet have been challenging. Despite numerous observational attempts, clarity on its existence remains elusive. However, a new wide-angle telescope under construction could soon play a pivotal role in solving this cosmic mystery when it begins operations in late 2025.

This telescope will survey the entire available sky every few nights, potentially providing definitive evidence regarding Planet Nine. Whether it is found or not, the data collected will significantly enhance our understanding of distant solar system objects and inform our broader understanding of planetary formation.

Understanding any new solar system planets is crucial as they serve as models for studying exoplanets around other stars. The potential discovery of a super-Earth or any new celestial body would provide valuable insights into planetary systems throughout the galaxy, highlighting the dynamic nature of scientific knowledge and its continual evolution.