Spaceflight Insider

News Archive / Tagged: Sedna

  • Data on 2 distant asteroids tease possibility of massive planet

    Laurel KornfeldFebruary 25th, 2017

    Observations of two extreme trans-Neptunian objects (ETNOs) suggest they were once part of a binary asteroid system that was perturbed by one or more undiscovered "super-Earth" planets that may still be lurking even further in the outer Solar System.