The first well-resolved image of the faraway chunk of rock fleetingly visited by NASA’s New Horizons spacecraft on New Year’s Day reveals the object — officially named 2014 MU69 but nicknamed Ultima Thule — is made of two lobes scientists say came together in an ancient slow-speed collision just as the solar system’s planets were forming.

Artemis 2 commander Reid Wiseman, Victor Glover, Christina Koch and Canadian astronaut Jeremy Hansen, in pre-flight medical quarantine at the Johnson Space Center in Houston, had hope to fly to Florida Tuesday to begin final preparations for launch. Instead, they will remain in Houston and rejoin family, friends and co-workers.

Building on a mission canceled last year, NASA is developing a mobile robot named VIPER for launch in 2022 to scout for water ice at the moon’s south pole, the same region where the agency aims to land astronauts by 2024.