The vast expanse of the solar system has always intrigued astronomers, pushing the boundaries of human understanding. In 2018, the discovery of 2018 VG18, nicknamed “Farout,” marked a significant milestone in this quest, as it became the most distant solar system object ever observed at the time. This groundbreaking finding underscored the mysteries that lie at the farthest reaches of our cosmic neighborhood and deepened scientific curiosity about the formation and dynamics of our solar system.
The Discovery of Farout
The journey to uncover 2018 VG18 began on November 10, 2018, when astronomers Scott Sheppard, David Tholen, and Chad Trujillo utilized the Subaru Telescope at Mauna Kea Observatory in Hawaii. Farout was spotted at a staggering distance of about 120 astronomical units (AU) from the Sun. To put this into perspective, Pluto orbits the Sun at an average distance of 39 AU. At three times farther than Pluto, Farout is an extreme outlier in terms of solar system objects.
What made this discovery so remarkable was not just its distance but the nature of the object itself. Initial observations showed it moving incredibly slowly across the night sky, indicative of its immense distance. Follow-up studies allowed scientists to confirm its orbit and begin uncovering details about its characteristics.
What Is Farout?
Farout is classified as a trans-Neptunian object (TNO), specifically within the scattered disk region, where icy remnants from the solar system’s formation continue to orbit the Sun. This classification highlights its unique role in helping scientists study the outermost layers of the solar system.
It is estimated that Farout is around 500 kilometers in diameter, meaning it is likely spherical and potentially qualifies as a dwarf planet. Its pinkish coloration, commonly associated with ice-rich objects, suggests its composition is primarily frozen water and other volatiles. As the Sun’s light barely reaches this distant object, its surface remains frozen, preserving clues about its history.
Farout’s orbit is elliptical, and its semi-major axis measures approximately 81 AU. With an orbital period exceeding 1,000 Earth years, it takes more than a millennium to complete a single revolution around the Sun. As of recent updates, Farout’s aphelion (its farthest point from the Sun) is projected to reach 124 AU in the coming decades, further cementing its status as one of the slowest and most distant known objects.
The Search for Planet Nine and Farout’s Role
Farout wasn’t discovered in isolation—it was part of a broader mission to identify objects that might offer evidence for the existence of the hypothetical Planet Nine. Planet Nine is theorized to be a massive, yet unseen planet lurking in the outer solar system, influencing the orbits of distant objects through its gravitational pull.
Farout’s discovery added to a growing catalog of extreme trans-Neptunian objects whose unusual orbits and alignment continue to intrigue scientists. While Farout itself may not directly point to Planet Nine, its relationship to other TNOs strengthens the case for further investigation.
Challenges in Observing Distant Objects
The discovery of 2018 VG18 Farout demonstrates the remarkable advancements in astronomical tools and techniques. Observing objects at such distances requires telescopes capable of capturing faint light signals and processing vast amounts of data. Farout’s identification relied on the Subaru Telescope’s cutting-edge technology and the determination of the astronomers involved.
However, challenges persist. Objects like Farout move slowly and are extremely faint, making it difficult to study their properties in detail. Additionally, tracking their orbits over long periods is necessary to gain a complete understanding of their trajectories and interactions with other solar system objects.
Implications for Understanding the Solar System
Farout’s discovery has profound implications for our understanding of the solar system’s architecture and its origins. By studying objects in the scattered disk, scientists can piece together clues about how the solar system evolved over billions of years. TNOs like Farout provide valuable insights into the gravitational influences of planets and the Sun, as well as the distribution of material during the solar system’s formation.
Moreover, Farout helps researchers explore questions about the limits of the solar system. Its location represents the edge of where the Sun’s gravitational dominance remains significant, offering a glimpse into the transition to interstellar space.
The Fascination of Uncharted Territory
While Farout’s discovery is a scientific achievement, it also highlights the uncharted mysteries that await in the cosmos. Its sheer distance from the Sun reminds us that the solar system is far larger and more complex than previously imagined.
Astronomers are continually pushing the limits of exploration, hoping to identify even more distant objects and uncover secrets about the forces shaping our celestial environment. Farout serves as a stepping stone in this pursuit, inspiring curiosity about what lies beyond the edge of our solar system.
Farout’s Legacy
The identification of 2018 VG18 Farout represents humanity’s quest to explore the unknown and expand its understanding of the universe. As astronomers continue to study this trans-Neptunian object, they will uncover deeper insights about the solar system’s outer regions and the interplay of gravity and motion. Farout’s discovery is a reminder that there is always more to learn and that the cosmos remains an infinite source of wonder.
Farout may reside at the very edge of the solar system, but its impact on scientific inquiry reaches far beyond. It challenges us to keep searching, keep questioning, and keep exploring the vast universe we inhabit.
by Dr. Bertalan Mesko, PhD
