Hubble and Webb find ancient space rocks that hold solar system secrets

Astronomers used two powerful space telescopes to look at very small and faint objects far beyond the orbit of Neptune. By combining the strengths of both observatories, researchers found 27 previously unknown bodies. These frozen objects are remnants from the early days of the solar system and offer clues about how planets first took shape.

Looking at Distant Objects

The research teams focused on trans-Neptunian objects, which are tiny bodies traveling far from the Sun. One telescope captured visible light while the other recorded infrared light at the same time. This combined approach allowed scientists to estimate the sizes of these faint bodies, figure out their orbits, and study their surface colors.

Surprising Similarities

Researchers looked at two different groups of these distant objects based on how they move. One group stayed near where they formed, while the other group was scattered outward long ago by shifting giant planets. Despite having very different histories, both groups showed similar surface colors and size patterns. Scientists expected smaller objects to look different due to repeated collisions over billions of years, but the surfaces appeared to retain their original characteristics.

Missing Small Objects

The survey also revealed a shortage of very small objects compared to what some existing theories predicted. The most sensitive instruments were needed to spot these extremely dim bodies, which shine millions of times more faintly than anything visible to the naked eye. Learning why fewer small objects exist will help researchers improve models of early planet growth.