Rocky Planets (Terrestrial) Mercury-like — small, dense planets with lots of metal and extreme temperatures Mars-like — small rocky planets with thin atmospheres Earth-like — rocky planets with oceans and life-friendly conditions Super-Earth — bigger rocky planets than Earth Lava planets — worlds with extremely hot surfaces Carbon planets — carbon-rich rocky worlds Gas Giants Jupiter-like Hot Jupiter Cold Jupiter Super-Jupiter Ice Giants Uranus-like Neptune-like Dwarf Planets Pluto-like Eris-like Ceres-like Haumea-like Makemake-like Fictional dwarf planets Moons Earth-like moons Ice moons Ocean moons Volcanic moons Captured moons Artificial moons (if you allow sci-fi) Main Sequence Stars (normal stars) Red dwarf — small, cool, very common stars Orange dwarf — between red dwarfs and Sun-like stars Yellow dwarf — Sun-like stars White star — hotter main-sequence stars Blue star — very hot, massive stars Giant Stars Red giant — an older star that has expanded Blue giant — huge, hot, short-lived star Yellow giant — larger and brighter than Sun-like stars Supergiant — extremely large stars Hypergiant — among the biggest stars known Rare / Special Stars Wolf–Rayet star — extremely hot star losing lots of material Variable star — brightness changes over time Pulsating star — expands and contracts Binary/triple star — stars orbiting other stars Population II star — old stars with fewer heavy elements Population III star — hypothetical first-generation stars End-of-Life Stars Red supergiant (before collapse) Supernova star (during the explosion event) Brown Dwarfs Normal Brown Dwarf — a typical brown dwarf that formed like a star but wasn’t massive enough to ignite normal hydrogen fusion. Planet-Forming Brown Dwarf — a brown dwarf with its own disk of dust and gas where planets or moons could form. J1407b-like — inspired by J1407b, a possible giant planet/brown dwarf with an extremely large ring system. Young Brown Dwarf — still glowing from leftover heat from its formation. Old Brown Dwarf — colder and darker after cooling for billions of years. Binary Brown Dwarf — two brown dwarfs orbiting each other. Black Holes Mini Black Hole — small black holes (for normal areas) Stellar Black Hole — formed from a massive star Intermediate Black Hole — between stellar and supermassive Supermassive Black Hole — giant black holes found in galaxy centers Special Galactic Objects Active Galactic Nucleus (AGN) — a bright, energetic region around a feeding supermassive black hole Quasar — an extremely bright active galactic center Black Hole System — a black hole with stars, planets, or other objects orbiting it White Dwarfs Normal white dwarf — the leftover core of a Sun-like star Hot white dwarf — young and extremely hot Cooling white dwarf — older and dimmer Black Dwarfs Black dwarf — a theoretical future stage of a cooled white dwarf (the universe is not old enough for any to exist yet) Neutron Stars Normal neutron star — ultra-dense stellar remnant Pulsar — a neutron star that sends out beams of radiation as it spins Magnetar — a neutron star with an incredibly strong magnetic field
