Is a Hidden Planet Lurking in Our Solar System's Oort Cloud?

A new study suggests that there is a small chance that a captured planet, most likely an ice giant around the size of Neptune, could be hiding in the Oort Cloud of our solar system. The researchers found that a planet could be ejected from one young solar system and then captured by another, with a small percentage of cases resulting in the planet being slowed down enough by the gravitational pull of another star to be captured in its Oort Cloud. The chances of a planet from our own solar system ending up in our Oort Cloud are estimated to be about 7%. However, the hypothesized Planet X is unlikely to be a captured planet in the Oort Cloud, as it is expected to be much farther from the sun than the Oort Cloud.