A theoretical spherical cloud of icy objects surrounding the Sun at 2,000-100,000 AU. Thought to be the source of most long-period comets. Never directly observed, but its existence is inferred from comet orbits.
A circumstellar disc in the outer solar system from Neptune's orbit (30 AU) to about 50 AU. Home to Pluto and many icy b...
An icy small body that, when passing close to the Sun, releases gases in outgassing, producing a visible coma and someti...
The gravitationally bound system of the Sun and everything orbiting it: eight planets, dwarf planets, moons, asteroids, ...
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