Pluto Smaller Than Eris

Newly discovered dwarf planet Eris is actually 1.27 times as large as the planet Pluto by mass. Both are in the distant outer solar system. Earth's moon is more than four times as large as either of them.

The complete list of the only star, all known planets, all known dwarf planets, and all satellites of 1,000 km in diameter or more in the solar system is as follows (in km):

Sun (Star) 1,393,000
Jupiter (Gas Giant) 142,992
Saturn (Gas Giant) 120,536
Uranus (Gas Giant) 51,118
Neptune (Gas Giant) 49,528
Earth (Terrestial Planet) 12,756
Venus (Terrestial Planet) 12,104
Mars (Terrestial Planet) 6,805
Ganymede (Jupiter) 5,262
Titan (Saturn) 5,151
Mercury (Terrestial Planet) 4,880
Callisto (Jupiter) 4,821
Io (Jupiter) 3,660
Moon (Earth) 3,474
Europa (Jupiter) 3,122
Triton (Neptune) 2,707
Eris (Dwarf Planet Trans-Neptune) 2,400-3,000
Pluto (Dwarf Planet Trans-Neptune) 2,306
Easterbunny (Possible Dwarf Planet Kuiper Belt) 1,660-2,000
Titania (Uranus) 1,578
Rhea (Saturn) 1,529
Oberon (Uranus) 1,522
Santa (Posible Dwarf Planet Kuiper Belt) 1,500
Iapetus (Saturn) 1,472
Charon (Pluto) 1,212
2002 TC302 (Possible Dwarf Planet ca. Kuiper Belt) under 1,200
Sedna (Possible Dwarf Planet ca. Kuiper Belt) 1,180-1,800
Umbriel (Uranus) 1,169
Ariel (Uranus) 1,158
Dione (Saturn) 1,123
Tethys (Saturn) 1,066
Ceres (Dwarf Planet Asteroid Belt) 975
Quaoar (Possible Dwarf Planet Kuiper Belt) 989-1346
Orcus (Possible Dwarf Planet Trans-Neptune) 880-1880