The trojan asteroid (3548) Eurybates, one of the targets of NASA’s upcoming Lucy mission, has a tiny moon. This image of Eurybates and its moon (circled) was captured by Hubble’s Wide Field Camera 3 (WFC3) on September 14, 2018. Image credit: NASA / ESA / Hubble / Noll et al, arXiv: 2008.01858. Trojan asteroids follow the same orbit as a planet, but stay either around 60 degrees ahead or 60 degrees behind along the orbit. Earth has one trojan...
