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The powerful space telescope zoomed in on Mors-Somnus, a binary pair of icy asteroids that originated within the Kuiper Belt
In examining a pair of icy asteroids at the edge of the Solar System, the James Webb Space Telescope is helping scientists understand the evolution of the ice giant Neptune. These findings could also help reveal how the ancient Earth grew saturated with water, the ingredient that ultimately led to the emergence of life. The binary asteroid system Mors-Somnus was recently discovered to have originated within an icy band of objects that make up what’s known as the Kuiper Belt. This region exists beyond the orbit of Neptune, the eighth and farthest planet from the Sun. Mors-Somnus can therefore be used as a proxy to study the dynamic history of Neptune, as well as other icy bodies in the Kuiper Belt, also known as trans-Neptunian objects (TNOs).
Some larger TNOs have been investigated in detail before, but this research, conducted as part of the Discovering the Surface Composition of TNOs (DiSCo-TNOs) program, represents the first time the surface composition of two parts of a small, binary pair of TNOs have been investigated. It’s also the first time that their chemical compositions have been revealed. “We are studying how the actual chemistry and physics of the TNOs reflect the distribution of molecules based on carbon, oxygen, nitrogen and hydrogen in the cloud that gave birth to the planets, their moons and the small bodies,” Ana Carolina de Souza Feliciano, research leader and DiSCo-TNOs program scientist at the Florida Space Institute, said. “These molecules were also the origin of life and water on Earth.”
Binaries like Mors-Somnus are rare finds outside of the Kuiper Belt. This is because the gravitational bond between such distantly separated binaries is disturbed when they are not protected by other icy bodies and fragments within the belt. This indicates to the team that the process by which Mors-Somnus was transported to its current position outside the Kuiper Belt must have been relatively slow. De Souza Feliciano and her colleagues used Webb to compare the surface of Mors-Somnus to the surfaces of six other undisturbed TNOs, or ‘cold classical’ ones, to determine that they have many commonalities. This revealed that these cold, classical bodies, as well as the asteroids Mors and Somnus, all formed around 2.7 billion miles away
