The quest to unlock the secrets of the Solar System continues to push scientists towards new areas of study, particularly asteroids and other celestial bodies orbiting our Sun. NASA's OSIRIS-REx mission has made a remarkable discovery on the 4.5 billion-year-old asteroid Bennu: the presence of water and carbon, fundamental elements for life on Earth.
Among the objects of interest are the mini-moons, these small asteroids temporarily captured by Earth's gravity, providing a unique window into the past. According to Richard Binzel, a professor of planetary sciences, these celestial bodies have a complex history of navigating through the inner solar system, bouncing in cosmic ricochets before being drawn into Earth's orbit.
The OSIRIS-REx mission.
Credit: NASA/GSFC
These mini-moons are considered ideal candidates for exploring the origins of our Solar System. Their proximity to Earth offers a less expensive and faster opportunity for exploration and sample collection missions. The leading theory suggests that these mini-moons originate from the asteroid belt located between Mars and Jupiter, making them perfect conservators of the Solar System's primitive conditions.
The retrieval of samples from these bodies is crucial to advance our understanding of space. The Japanese space agency (JAXA), for example, managed to obtain samples from the asteroid Ryugu in 2019, revealing the presence of prebiotic organic matter and amino acids, thus providing clues about the essential components for life.
These sample return missions, like that of OSIRIS-REx, are critical for studying volatile and organic materials, which are often difficult to analyze after passing through Earth's atmosphere.