Planet the Size of Uranus Might Be Trapped in Our Solar System’s Outskirts

According to a recent study featured in The Independent, astronomers predict that there could be alien planets as large as Jupiter or Uranus lurking in the distant fringes of our solar system, beyond the proposed location of the hypothetical Planet X.

These planets, originating from outside our solar system, could be ensnared within the Oort Cloud. This hypothetical boundary of our solar system is envisaged as a shell of debris marking the gravitational limit of the Sun and its planets.

The researchers, including a team from the French National Centre for Scientific Research (CNRS), believe that there could be a greater number of interstellar objects in this remote region of the solar system than initially anticipated.

To investigate this, the scientists employed complex computer simulations to understand how solar systems could eject large planets and how another planetary system might capture such a wandering “orphan” planet. It appears that a delicate balance of energy is required for this process – a certain threshold of kinetic energy is needed for a planet to escape the gravitational pull of its original star, and a significant amount of energy is also required for another star system to capture it.

The simulations indicate that a tiny fraction of such celestial encounters could result in a star’s gravitational field ensnaring a castaway “orphan” planet, essentially adopting it.

This type of capture is more probable when such a planet drifts near to the outer edge Oort Cloud of a star system. Considering that up to a tenth of a star’s original planets are likely to be thrown into deep space, the scientists estimate that there is a 7% chance of our solar system harboring an ice giant planet, similar to Uranus, within the Oort Cloud.

While these estimates suggest that “one in every 200-3000 stars could host an Oort cloud planet,” the researchers caution that this is likely an overestimate. It does not consider the instabilities that occur in the early stages of a solar system that could impact its star birth cluster or the stripping away of planets by passing stars.

The analysis suggests that the planets potentially located at the edge of our Solar System within the Oort Cloud are more likely to have been captured from interstellar space rather than being an offspring of the Sun. As scientists continue to explore the outer reaches of our solar system, these findings could radically alter our understanding of our own cosmic neighbourhood.