--- title: "Astronomers Surprised After Finding Tiny Moon Is Actually Two Tiny Moons in a Trenchcoat" description: "NASA scientists believe that a small asteroid in the Main Asteroid Belt called \"Dinky\" birthed its own Moon. Actually, two of them." date: "2024-05-31" modified: "2024-05-31" authors: - name: "Maggie Harrison Dupré" job_title: "Senior Staff Writer" link: "https://futurism.com/authors/mharrison" url: "https://futurism.com/the-byte/two-tiny-moons-glued-together" categories: - "Astronomy" - "Moon" - "Space" tags: - "asteroid belt" - "asteroids" - "NASA" - "the digest" --- # Astronomers Surprised After Finding Tiny Moon Is Actually Two Tiny Moons in a Trenchcoat ![NASA scientists believe that a small asteroid in the Main Asteroid Belt called "Dinky" birthed its own Moon. Actually, two of them.]() *\Image: NASA\* ## That's Dinky to You Last year, images taken by NASA's [Lucy]() spacecraft [revealed that]() a tiny moon that orbits an asteroid nicknamed "Dinky" is, in fact, *two* tiny moons fused together. The finding baffled scientists, who had never witnessed this kind of satellite, known as a contact binary, orbiting an asteroid. But thanks to new research, we might be getting closer to piecing together the strange cosmic puzzle. A new NASA study about the strange Dinky discovery, [published this week in the journal *Nature*](), posits that the mid-size asteroid likely birthed one or both mini-moons — together dubbed "Selam" — itself. Cosmic twins! The NASA researchers behind the study believe that the findings offer a fascinating new glimpse into the mysterious, and surprisingly elaborate world of smaller cosmic bodies. "There's a lot more complexity in these small bodies than we originally thought," said University of Maryland astronomy professor and study coauthor Jessica Sunshine in a [statement](). https://www.youtube.com/watch?v=aE3ixq2yrcw&t=1s ## Cosmic Dance At the time of Lucy's visit to Dinky — given name [Dinkinesh]() — in November 2023, it was the smallest body ever closely examined by humankind within the main asteroid belt between Mars and Jupiter. At first, [as *Space.com* reported at the time](), Dinky was believed to be a type of contact binary — a not-too-rare phenomenon in which two celestial bodies orbit each other in an extremely close cosmic dance. But when scientists looked closer at Selam, they were shocked to discover that the satellite was a bizarre, unprecedented contact binary *within* a contact binary. Or, as *Space.com* [put it more recently](), a "contact-binary-asteroid-moon situation." Examining Dinky's surface, though, seems to have shed some light on the rare throupling. As explained in the study, the astronomers believe that the small asteroid started spinning fast enough for some of its loosely-bonded material to break off. Some of that material stayed in orbit around the young space rock and fused into two small, separate satellites. How the moons later combined into one is still a mystery, but it's likely they moved closer over time until they eventually melded together. We wish this delightfully strange celestial family all the best — and, to Sunshine's point, we hope that this research leads to further study into the weird world of smaller space rocks down the line. **More on space:** [*Astronomers Spot Epic Flows of Lava Oozing out of Venus*]() ## Author At Futurism, I've reported extensively on the rise of AI as a cultural and business force shaping the media industry, and more broadly how those dynamics are changing how we all consume and share information and relate to one another. I'm also fascinated by public health policy and ethics, the role of emerging tech in politics and governance — and the powerful people and forces at those intersections — climate change, and the environment. My investigation on Sports Illustrated's use of AI-generated authors with fictional biographies won a 2024 Mirror Award for "Best Story on Media Coverage of Artificial Intelligence in Journalism and the Media" from Syracuse University's SI Newhouse School, I contributed to Niemen Lab's 2025 Predictions for Journalism series, and I've discussed my work for Futurism during appearances on NPR, CNN, the BBC, the CBC, and more. I grew up in rural Pennsylvania and attended the University of Massachusetts Amherst, where I played Division I field hockey for the Minutewomen as a midfielder. Since then, I've lived in New Orleans, Louisiana and Manhattan, New York. I spend my free time running, reading, perusing archival fashion, and searching for the world’s best negroni. I also have a debonair tuxedo cat, Westley, who's named after "The Princess Bride." ### Author social links [Bluesky]()