“Lucy’s Baby” asteroid is a toddler of the solar system

Credit: NASA/Goddard/SwRI/Johns Hopkins APL/NOIRLab for the original images/Brian May/Claudia Manzoni for stereo processing of the images.

A group of scientists led by Cornell University has unveiled a remarkable discovery about an asteroid known as “Lucy’s baby,” found orbiting another asteroid last November.

Through innovative calculations, they estimate that this asteroid, named Selam, is a mere 2-3 million years old, making it one of the youngest members of our solar system.

These findings, published in Astronomy & Astrophysics, provide valuable insights into the formation and evolution of asteroids, enhancing our understanding of the solar system’s history.

Selam’s age was determined using a new method based on its dynamic behavior in space, rather than traditional techniques like analyzing surface craters. The team’s calculations align with NASA’s Lucy mission’s analysis, confirming Selam’s youthful age.

One advantage of this new method is its ability to estimate ages without requiring close-up images from spacecraft, making it a cost-effective and efficient approach.

It also offers a way to study secondary bodies in binary asteroid systems, which account for a significant portion of near-Earth asteroids.

Lead researcher Colby Merrill, along with his team, utilized their expertise in dynamics to model the interaction between Selam and its parent asteroid, Dinkinesh.

They found that the gravitational forces and solar radiation acting on the system play a crucial role in shaping Selam’s orbit and age.

Binary asteroids like Selam-Dinkinesh are dynamic and complex, engaging in a gravitational tug of war that affects their evolution over time. By understanding these dynamics, scientists can gain insights into the processes shaping our solar system.

The researchers’ calculations suggest that Selam formed relatively recently from material ejected by Dinkinesh, indicating ongoing processes of asteroid formation and evolution.

This discovery contributes to our understanding of how binary systems are created and evolve over time.

Interestingly, Selam’s estimated age makes it younger than the famous human-ancestor fossil after which it is named.

The fossil, known as “Selam” or “Lucy’s baby,” is approximately 3.3 million years old, whereas the asteroid Selam is estimated to be 2-3 million years old.

Moving forward, the researchers aim to apply their method to other binary asteroid systems to further refine our understanding of asteroid ages and dynamics.

By combining different age-dating techniques, scientists can enhance the accuracy of their estimates and gain deeper insights into the history of our solar system.

Overall, the discovery of Selam’s age offers a fascinating glimpse into the ongoing processes of asteroid formation and evolution, highlighting the dynamic nature of our solar system’s celestial bodies.

Source: Cornell University.