Asteroid dust reveals solar system origins

A dust sample collected from the asteroid Bennu has revealed information about where and how the building blocks of our solar system came together. The findings suggest that materials from different regions of the early solar system mixed to form planets and other celestial bodies.

Bennu’s size and orbit

The asteroid Bennu has a diameter of approximately 500 meters and orbits the sun in just over a year. Its relatively small size and orbit make it a valuable target for studying the early solar system's history.

Osiris-Rex mission returns samples

The American spacecraft Osiris-Rex approached Bennu, collected a small amount of its surface, and brought back about 120 grams of dust and small rocks to Earth. This mission marked the first U.S. attempt to collect samples from an asteroid and return them to Earth.

Bennu’s ancient grains

These Bennu grains have remained intact since 4.5 billion years ago, making them valuable archives of the birth of planets. Their preservation provides a rare glimpse into the conditions of the early solar system.

Distinct origins of Bennu’s material

A team from the Swiss Federal Institute of Technology in Zurich analyzed half a gram of this dust and discovered that Bennu has two distinct origins, coming from regions close to the sun and from distant, icy regions. This suggests the asteroid is a mix of materials from different parts of the solar system.

Jupiter’s role in solar system formation

Jupiter played an important role in the formation of the solar system by blocking large grains and allowing fine dust to pass, thus enabling materials from both regions to mix. This process may explain how diverse materials combined to form planets.

Venus’s composition and solar connection

The composition of Venus is very similar to that of the sun itself, which could make it a privileged witness to the original recipe of rocky planets. This similarity hints at the processes that shaped the inner planets.

Japan’s upcoming Mars moon mission

Japan is preparing to send a probe to Phobos, a moon of Mars, to also bring back samples. This mission aims to further our understanding of the solar system’s formation by analyzing extraterrestrial materials.

Bennu dust and the origin of life

The dust brought back by Bennu brings us closer to a major question: where do we come from? By studying these ancient materials, scientists hope to uncover the origins of the solar system and the building blocks of life itself.