SEEING DOUBLE by Jeff Hecht PRIMITIVE WORLD The Kuiper Belt object 2014 MU69 (now officially named Arrokoth) is a contact binary, each lobe a hodgepodge of smaller regions. Scientists think this is the most unchanged object from the solar system's formation that a spacecraft has so far encountered. Binary Worlds 6 contact binary comets Mercury 127 180 3 Mars crossing asteroids main-belt asteroids (1 co-classified as a comet, 11 are contact binaries) Jupiter Trojan asteroids (at L4 ) (1 is a contact binary) Earth Mars Asteroid belt Jupiter Venus 1 contact binary inside Earth's orbit NOT TO SCA LE 34 28 near-Earth asteroids (55 are contact binaries) FEBRUARY 2 02 0 * SK Y & TELESCOPE 4 Jupiter Trojan asteroids (at L5 ) (1 is a contact binary)