Comets: Dirty Snowballs from the Edge of Space

Comets are icy bodies made of rock, dust, and frozen gases.
They are often called dirty snowballs because of their icy, dusty makeup.
Most comets come from the Kuiper Belt and Oort Cloud at the solar system’s edge.
A comet’s tail always points away from the Sun, pushed by solar wind.
The bright coma forms when sunlight heats the comet’s surface, releasing gas and dust.
Some comets, like Halley’s Comet, return on predictable orbits visible from Earth.
A comet’s nucleus is typically just a few miles wide, though tails can stretch millions of miles.
Ancient cultures saw comets as omens, both good and bad.
NASA’s Rosetta mission landed a probe on Comet 67P, revealing detailed surface features.
Comets may have delivered water and organic molecules to early Earth, aiding life’s origins.