Scientists have made a groundbreaking discovery about how our solar system could potentially capture a new planet. According to a research note in Celestial Mechanics and Dynamical Astronomy, our solar system can capture an interstellar object (ISO) or a rogue planet, which could lead to a significant change in our cosmic neighbourhood. The study is titled 'Permanent Capture into the Solar System' and authored by Edward Belbruno from Yeshiva University's Department of Mathematical Sciences and James Green, formerly of NASA and currently with Space Science Endeavours.
Phase Space
The key to this phenomenon lies in the concept of phase space, a mathematical representation that describes the state of a dynamical system like our solar system. This complex framework, rooted in Hamiltonian mechanics, combines coordinates of position and momentum, effectively mapping all possible orbital configurations around the Sun. Key factors such as orbital eccentricity, semi-major axis, and orbital inclination all contribute to the phase space landscape.
Solar System's phase space
Our Solar System's phase space features two types of capture points: weak and permanent. Weak capture points are areas where objects can be temporarily drawn into semi-stable orbits. These points often occur at the intersection of gravitational boundaries between celestial bodies. They provide a gravitational "nudge" rather than a stable orbital adoption.
Permanent capture points, on the other hand, are regions where objects can be permanently captured into stable orbits. This occurs when an object's angular momentum and energy align in a precise configuration, allowing it to maintain a stable orbit.
The phase space of our Solar System is highly complex, involving numerous moving bodies and constantly changing coordinates. Subtle variations in these coordinates can cause objects to transition between permanent and weak capture states. Similarly, minor differences in the characteristics of interstellar objects (ISOs) or rogue planets can lead them into these capture points, potentially altering the dynamics of our Solar System.
"The permanent capture of a small body, P, about the Sun, S, from interstellar space occurs when P can never escape back into interstellar space and remains captured within the Solar System for all future time, moving without collision with the Sun," the researchers wrote.
"In addition to being permanently captured, P is also weakly captured," they added.
Researchers have identified openings in the Sun's Hill sphere, a region where the Sun's gravity dominates, which could allow ISOs or rogue planets to enter into a stable orbit around the Sun.
"Permanent weak capture of interstellar objects into the Solar System is possible through these openings. They would move chaotically within the Hill's sphere to permanent capture about the Sun taking an arbitrarily long time by infinitely many cycles," the authors state. These objects would never collide with the Sun and could be captured permanently.
