The advent of the James Webb Space Telescope has improved our "gaze" on the most distant stars, but we may have overlooked a secret hidden right under our noses. The Kuiper Belt, known for its icy bodies, could hide much more than we imagined.
Astronomers are on the trail of a planet the size of Earth, hidden right in this region. This discovery could rewrite what we know about our cosmic neighborhood. What if we had an unexpected neighbor?
A mystery in our cosmic backyard
The Kuiper Belt, the region of our Solar System located beyond Neptune, spans about 30-55 astronomical units (one astronomical unit, or AU, equals the distance from the Earth to the Sun).
This region, filled with countless icy bodies and over a trillion comets boasts Pluto as its most precious jewel. But, like any good mystery, it could still hide some surprises.
A team of Japanese astrophysicists, with keen eyes and precision instruments, noticed something strange and described it in a study published in The Astronomical Journal (I link it here). Some objects in the Kuiper belt were not moving as they should. These irregularities suggest the gravitational influence of a more massive celestial body: put simply, these anomalous movements could be explained by the presence of a planet in that region.
A new neighbor in the Kuiper belt
The alleged planet, called “Kuiper Belt Planet (KBP)”, would be located approximately 200-500 AU from the Sun. Unlike the theorized Planet X, which could be between 400 and 800 AU from the Sun, this planet would have a mass 1,5 to 3 times that of Earth. For reference, Pluto is located 39 AU from Earth.
Patryk Sofia Lykawka of Kindai University e Takashi Ito from the National Astronomical Observatory of Japan wrote: “We predict the existence of an Earth-like planet. It is plausible that an early planetary body could survive in the distant Kuiper Belt as a Kuiper Belt Planet (KBP), since many such bodies existed in the early solar system.”
The hunt continues
Finding new planets is no walk in the park. For exoplanets outside our Solar System, astronomers monitor the dimming of light as these planets transit in front of their stars. But within our system, the hunt becomes even more complex, requiring precise observations of celestial movements. For example, the discovery of Neptune occurred when Urban Le Verrier identified an orbital anomaly with Uranus, deviating from Newtonian predictions. Confirming his suspicion, the German astronomer Gottfried Galle he found Neptune right where Le Verrier predicted.
This is to say that the existence of another planet in the Kuiper belt theorized by Japanese astronomers is a fascinating hypothesis, but at the moment only a hypothesis. Further observations will be needed to truly confirm this.
