Asteroid Bennu's samples suggest an unexpected origin involving Jupiter, according to a study published in Science Advances. Bennu, which orbits the sun once every 1.2 years and comes close to Earth every six years, was sampled by NASA's OSIRIS-REx probe in 2023. The probe collected around 120 grams of material, part of which was sent to ETH Zurich for analysis by Maria Schönbächler, a professor of isotope geochemistry. Her team examined isotopes of iron, titanium, and chromium, uncovering a chemical signature that links Bennu to another asteroid, Ryugu, and to CI meteorites—rare, carbon-rich meteorites found on Earth. These objects share similar isotopic fingerprints, suggesting they all formed from the same reservoir of cosmic dust. This discovery challenges earlier beliefs that Bennu originated in the outer regions of the solar system. Instead, the data indicate that Bennu, Ryugu, and the CI meteorites formed near the "water-ice line," a boundary in the early solar system where water vapor begins to freeze. This zone, located about 2.7 astronomical units from the sun (roughly the distance of Mars), is thought to have been a mixing point for materials from both the inner and outer parts of the solar system 4.5 billion years ago. Schönbächler and her colleagues suggest that Jupiter played a crucial role in this mixing. As the largest planet in the solar system, Jupiter formed early and may have acted like a "bridge pillar," facilitating the movement of fine dust between different regions. This process allowed materials from various parts of the solar system to blend near the water-ice line. As a result, Bennu's material contains a high amount of water and has a chemical composition similar to the sun, indicating that the dust surrounding the young sun was thoroughly mixed. The study highlights Bennu's potential as a window into the original chemical composition of the early solar system. Its material is believed to date back to the solar system's formation and has remained largely unaltered. The asteroid's water and organic content also provide clues about how Earth might have acquired the building blocks of life. Schönbächler is now looking forward to the Japanese mission to Phobos, Mars’ moon, which is scheduled to launch at the end of October. She plans to request access to analyze the samples once they return to Earth in 2031.