James Webb Space Telescope Reveals Clues About Neptune’s Evolution and Earth’s Water Origins
The James Webb Space Telescope (JWST) has made a groundbreaking discovery that sheds light on the evolution of Neptune and the origins of water on Earth. By examining a pair of icy asteroids located at the edge of the solar system, scientists have gained valuable insights into the history of Neptune, an ice giant, and how ancient Earth became saturated with water, a crucial ingredient for the emergence of life.
The binary asteroid system, named Mors-Somnus, was recently found to have originated within the Kuiper Belt, a region beyond the orbit of Neptune. The Kuiper Belt is composed of icy objects known as trans-Neptunian objects (TNOs), and studying Mors-Somnus provides a proxy for understanding the dynamic history of Neptune and other icy bodies in this region.
While larger TNOs have been extensively studied in the past, the JWST’s Surface Compositions of Trans-Neptunian Objects (Disco-TNOs) program marks the first time that the surface composition of a small, binary pair of TNOs has been investigated. This groundbreaking research has revealed the chemical compositions of these asteroids for the first time.
“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,” explains Ana Carolina de Souza Feliciano, research leader and Disco-TNOs program scientist at the Florida Space Institute. “These molecules were also the origin of life and water on Earth.”
Binaries like Mors-Somnus are rare outside the Kuiper Belt due to the gravitational bond between distantly separated binaries being disturbed when they are not protected by other icy bodies and fragments within the belt. This suggests 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 the JWST to compare the surface of Mors-Somnus with six other undisturbed TNOs, known as “cold classical” ones. This comparison revealed many commonalities, indicating that these cold, classical bodies and the asteroids Mors and Somnus all formed around 2.7 billion miles away in the same region of the Kuiper Belt. It is believed that other TNOs also formed in this region.
Furthermore, the fact that these bodies appear perturbed from their original positions in the Kuiper Belt allows scientists to compare them to undisturbed cold classical TNOs and potentially track down how Neptune migrated to its current orbit.
The Disco-TNOs program has been eagerly awaiting the delivery of data from the JWST, and the results from analyzing nearly 60 TNOs have exceeded their expectations. “As we started to analyze the Mors and Somnus spectra, more data were arriving, and the connection between the dynamic groups and compositional behavior was natural,” says de Souza Feliciano.
Noemí Pinilla-Alonso, a researcher at the Florida Space Institute and co-leader of the Disco-TNOs program, believes that the JWST’s unprecedented spectral observation capabilities will continue to provide valuable information about objects in the Kuiper Belt and even beyond Neptune in the future. “For the first time, we can not only resolve images of systems with multiple components, but we can also study their composition with a level of detail that only the JWST can provide,” she says. “We can now investigate the formation process of these binaries like never before.”
Although the JWST was primarily designed to observe objects in the early universe, such as galaxies and quasars billions of light-years away, de Souza Feliciano emphasizes that this research highlights the telescope’s versatility and pioneering role. “Before JWST, there was no instrument able to obtain information from these objects in that wavelength range,” she explains. “I feel happy to be able to participate in the era inaugurated by the JWST.”
The team’s groundbreaking research has been published in the journal Astronomy & Astrophysics, solidifying the JWST’s position as a trailblazer in the field of space exploration and discovery.
