In a groundbreaking study, researchers from Cornell University have estimated the age of an asteroid named Selam, which orbits another asteroid called Dinkinesh. Using novel statistical calculations based on dynamics, the researchers were able to estimate that Selam is between 2 and 3 million years old. This new method complements traditional methods such as analyzing surface craters and does not require expensive spacecraft for close-up images, making it more versatile.
The age of Selam is younger than the fossil of the human ancestor it is named after, a 3-year-old girl found in Ethiopia that is 3.3 million years old. This suggests continuous creation of binary asteroid systems and contributes to our understanding of the dynamics of these fascinating objects. The researchers now aim to apply their method to other binary systems and contribute to the field of asteroid research.
NASA’s mission Lucy, set to study Trojan asteroids in Jupiter’s orbit in 2027, will further advance our knowledge of the solar system. Binary asteroids like Selam and Dinkinesh are complex objects that engage in a tug-of-war due to gravity and radiation from the Sun. The researchers calculated that Selam formed from surface material ejected by Dinkinesh and reached its current state after around 3 million years. This age estimation method can be applied to other binary systems with well-characterized dynamics, providing valuable information about their formation and evolution.
