The universe as a whole can be viewed as a very intricate machine. With synchronized moving parts–planets spinning around their stars, gears turning in a clock–it works in a very complex way. Simultaneously, like a wrench being thrown in moving parts, there are wild cards that throw off the balance of these synchronized planets. The result of this mishap causes a relatively unexplored area of astronomy; rogue planets. 

Similarly to comets and asteroids, there are entire planets that are able to roam without being in a fixed orbit around the sun. Rogue planets are newer discoveries in the astronomy world, classified as being elusive and difficult to photograph. The reason for why these wandering planets exist is because they got pushed out of their own orbit by stronger gravitational forces. For years astronomers and researchers believed these dark, starless planets to be cold and inhospitable. However, due to the thick atmosphere of these planets, they could potentially trap heat under its surface causing a volcanic ground to cover the planet. This sort of hostile environment could only be lived in by the most tolerant organisms. But it's still life.  

What makes them so elusive and difficult to study, even more difficult to find evidence of life, is the darkness of the planet. Because it has no star, the surface of this planet is entirely dark, contributing to the main belief that this planet would be very cold. The only way this planet could be found is through microlensing. Microlensing is when astronomers observe the warped light rays that happen as a result of a rogue planet passing over a background star. It is rare to catch these allusive planets through microlensing alone. As a result, in 2027, NASA plans to launch Roman–a telescope that will be able to capture rogue planets in much higher detail. 

As we learn more about rogue planets, an interesting discussion comes up; could Earth ever become one? Furthermore, could Earth ever collide with one? Both are possibilities that have been researched, and both have the same answer; yes. In theory, Earth could become a rogue planet if it's orbit is tampered with, but this would most likely not occur from any natural process. However, this isn't to say that rogue planets are rare to occur. In fact NASA has recently speculated that the number of starless planets outnumber the star-bound planets by twenty times in our galaxy alone. This makes the latter question of possible collision with earth seem much more likely. While the possibility of a full head-on collision with a rogue planet would mean that our planet would end up completely destroyed, the vast size of the solar system suggests that it likely wouldn't happen. Rather, the introduction of the rogue planet could mess up the gravitational forces at play within our solar system, resulting in very uncomfortable and threatening changes in our planet's weather. Fortunately for Earth, these possibilities are very, very slim when we put into perspective how vast our universe is. Nevertheless, rogue planets continue to prove to be an interesting area of interest in the study of planets. 

References

Balzer, Ashley. “Unveiling Rogue Planets with NASA’s Roman Space Telescope.” NASA, 17 Aug. 2020, www.nasa.gov/feature/goddard/2020/unveiling-rogue-planets-with-nasas-roman-space-telescope.

“Can Life Exist on a Rogue Planet?” Discover Magazine, www.discovermagazine.com/the-sciences/can-life-exist-on-a-rogue-planet.

published, Paul Sutter. “Could Earth Ever Become a Rogue Planet?” Space.com, 29 July 2023, www.space.com/earth-become-rogue-planet-sun-death. Accessed 5 Sept. 2023.

Balzer, Ashley. “New Study Reveals NASA’s Roman Could Find 400 Earth-Mass Rogue Planets.” NASA, 14 July 2023, www.nasa.gov/feature/goddard/2023/new-study-reveals-nasa-s-roman-could-find-400-rogue-earths. Accessed 5 Sept. 2023.

“Space-Warping Planets: The Microlensing Method.” The Planetary Society, www.planetary.org/articles/space-warping-planets-the-microlensing-method.

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