Rank 37 documents Dawn — the Discovery Program mission that pioneered ion propulsion for deep-space orbit transfers and became the first spacecraft to orbit two extraterrestrial bodies. Launched 27 September 2007 aboard Delta II Heavy, Dawn's 747 kg bus carried NSTAR xenon ion engines that fired for years at millinewton thrust, delivering Chris Russell's UCLA/JPL team to 4 Vesta in July 2011 and 1 Ceres in March 2015. At Vesta, Dawn mapped the Rheasilvia impact basin and linked the body to HED meteorite families. At Ceres, the framing camera resolved Occator crater's bright salt deposits and Ahuna Mons cryovolcano — rewriting dwarf-planet geology. Extended low orbit continued until fuel depletion November 2018. Wallimilist renders Dawn centre with ion thruster glow, Ceres bright spots, Vesta inset, and orbital ellipse lines exactly as the master PNG dictates — dual-orbit kicker, cream-navy arch palette, and curator copy on ion drive efficiency and protoplanet science.