Asteroid Bennu Has an Identity Crisis, and Jupiter Might Be to Blame

Asteroid sample return missions have brought well-preserved samples of the early solar system back to Earth, but these samples sometimes provide more questions than answers. A new study from ETH Zurich and Lawrence Livermore National Laboratory found that asteroid Bennu appears to have been born in both the inner and outer solar system. The researchers analyzed the isotopes in Bennu's samples and found that its titanium and chromium isotopes matched those expected for CC asteroids, but its iron isotopes suggested a different origin. The study suggests that Jupiter may have influenced Bennu's formation by creating pressure ridges that trapped dust grains, leading to the formation of asteroids like Bennu.

• Researchers analyzed isotopes in Bennu's samples.
• The study found that Bennu's titanium and chromium isotopes matched CC asteroids, but its iron isotopes suggested a different origin.
• Jupiter's gravitational influence may have created pressure ridges that trapped dust grains, leading to the formation of asteroids like Bennu.

The research highlights the complexity of asteroid formation and the role of Jupiter in shaping the early solar system. Bennu's unique isotopic composition suggests it formed near the water/ice line, blending material from both the inner and outer solar systems. The study also notes that Bennu has migrated inward over millions of years, becoming a Near Earth Asteroid (NEA) and a prime target for sample return missions. The findings provide insights into the formation of asteroids and the role of planetary bodies in shaping the solar system.

AI-generated summary of the original article — see the source for the full story.