Tiny moon revealed as two in disguise; astronomers astonished
In a surprising revelation last year, astronomers discovered that a tiny moon orbiting an asteroid, fondly referred to as "Dinky," was actually two moons fused together. The images were taken by NASA's Lucy spacecraft. Now, a recent discovery by NASA, published in the journal Nature, suggests that the mid-size asteroid likely birthed one or both of these mini-moons, collectively named "Selam."
Unraveling the complexity of small celestial bodies
The NASA researchers who conducted the study believe that the findings provide an intriguing new perspective, into the unexpectedly complex realm of smaller celestial objects. "There's a lot more complexity in these small bodies than we originally thought," said Jessica Sunshine, a University of Maryland astronomy professor and study co-author. Dinky, officially named Dinkinesh, was the smallest body ever closely examined by mankind within the main asteroid belt between Mars and Jupiter. The Lucy spacecraft visited it in November 2023.
The formation and fusion of Dinky's mini-moons
The study suggests that Dinky began spinning fast enough for some of its loosely-bonded material to break off and stay in orbit around it, eventually fusing into two separate small satellites. However, the process by which these moons later combined into one remains unknown. It is likely they moved closer over time until they eventually melded together. This discovery challenges current theories about how asteroids and other celestial bodies form over time.
