NASA’s Lucy spacecraft, first launched in 2021 to explore the Trojan asteroids trapped near Jupiter, has made an interesting discovery. The spacecraft found an asteroid, nicknamed Dinky, that actually has a smaller asteroid orbiting it, as originally reported by Scientific American. That’s right. It’s basically a moon with its own moon. It’s an ouroboros of cosmic curiosity.
The technical term here is a binary asteroid pair and Dinky, whose real name is Dinkinesh, was spotted by Lucy during a quick fly by. That’s when the spacecraft spotted the smaller “moon” orbiting it.
“A binary was certainly a possibility,” Jessica Sunshine, a planetary scientist at the University of Maryland, told Scientific American. “But it was not expected, and it’s really cool.”
As a matter of fact, the fly by itself wasn’t supposed to find anything of note. It was simply a trial run for the team to hone its skills before investigating the aforementioned Trojan asteroids orbiting the sun ahead of and behind Jupiter. The team wanted to make sure Lucy’s probe would successfully latch onto a space rock, even when both objects were moving extremely fast. Guess what? It worked. Hal Levinson, a planetary scientist at the Southwest Research Institute and principal investigator of the Lucy mission, said that the test was “amazingly successful.”
As for Dinky and its, uh, even dinkier satellite, NASA scientists still have a long way to go with its investigation, as only about one third of the relevant data has been beamed down to Earth. NASA has released a series of images showing Dinky and its pseudo-moon, but not any actual data as of yet.
Even just from these images, however, you can tell a lot about these two celestial bodies. There’s a visible equatorial ridge on the main body of Dinky aka Dinkinesh and a secondary ridge-line branching off from it. The parent asteroid is covered in craters, likely the result of numerous hits by other asteroids. Levinson says that there are more images to come of the secondary satellite and that these pictures suggest that the junior asteroid has some “interesting” stuff going on. He goes on to say that the shape is “really bizarre.”
Binary asteroid pairs are not rare, as researchers have found that around 15 percent of near-Earth asteroids boast a cute lil orbital companion. NASA and affiliated researchers are still waiting for more data on the pair, including color images and spectroscopy that should shed some more light on the two asteroids. Levinson says “there’s a lot of cool stuff to come.”
In the meantime, Lucy will continue on its original mission, to investigate those mysterious Trojan asteroids near Jupiter. It’ll make contact with one in 2025.