New Horizons and the Hunt for a Flyby Target
NASA’s New Horizons spacecraft, which famously flew past Pluto in 2015 and later studied the distant KBO Arrokoth, is still active and moving deeper into the Kuiper Belt. The mission has already provided insights into Pluto’s surface, KBO chemistry, and the processes that shaped these icy worlds.
One of the main goals of this new survey is to find a potential flyby target for New Horizons before it leaves the Kuiper Belt for good. While the chances of finding a KBO in just the right location are small, the survey will still yield valuable data about the size, shape, and distribution of KBOs in this region, helping to piece together the history of our Solar System.
Mapping the Outer Reaches of the Kuiper Belt
The proposed survey will allow scientists to study the “deep Kuiper Belt”—a region farther out than what has been thoroughly explored. Some evidence suggests that there may be a significant number of distant KBOs, possibly forming a second belt beyond the currently known Kuiper Belt.
By using the Roman Telescope’s advanced instruments, astronomers can detect smaller and fainter objects than ever before. This will help determine how many small KBOs exist and whether they follow the same size distribution as those closer to Neptune. If fewer small objects are found than expected, it could challenge existing models of how these bodies formed.
Understanding Cratering, Formation, and Binaries
One way to study KBO formation is by looking at the craters on larger bodies like Pluto and Charon. These craters reveal the number of small objects that have impacted them over time. A lack of small craters could mean that fewer small KBOs exist than predicted by some theories.
Another key area of study is KBO rotation. By measuring how long these objects take to spin, scientists can learn about their internal structure and how they were formed. Some KBOs are also binary systems, meaning they exist as two objects orbiting each other. These binaries provide clues about how material in the outer Solar System clumped together to form planets and smaller bodies.
The Roman Telescope’s Unique Role
The Roman Space Telescope is ideal for this survey because it can observe the same region of the sky multiple times over two years, allowing astronomers to track KBO movements and determine their orbits. The telescope will scan a region near the Galactic Plane, a part of the sky that is usually too crowded with stars for ground-based telescopes to effectively search for faint moving objects.
To ensure accurate detections, researchers will use advanced image processing techniques to filter out background stars and pinpoint moving KBOs. The survey will require hundreds of hours of telescope time but is expected to discover around 900 new KBOs, including many too faint for any current ground-based surveys.
Beyond the Kuiper Belt: Additional Science Goals
While the primary goal of this project is to explore the Kuiper Belt, the survey could also contribute to exoplanet and microlensing studies. Since the telescope will be observing a dense star field, it could detect hot Jupiters and hot Neptunes—types of exoplanets that orbit close to their stars. Additionally, the data may help refine models of the Milky Way galaxy by improving measurements of stellar motions.
Conclusion: A Golden Opportunity
The Roman Galactic Disk survey represents a rare and exciting opportunity to explore the outer reaches of the Solar System like never before. By discovering and characterizing a large population of KBOs, this project will help scientists understand the formation of small icy worlds, test theories of planetary evolution, and possibly identify a final flyby target for New Horizons.
With its ability to reach deeper into space than previous surveys, the Roman Telescope is set to revolutionize our knowledge of the Kuiper Belt and beyond. Whether or not a new flyby target is found, the results will shape our understanding of the distant Solar System for years to come.
Source: Benecchi
