Comet
/ˈkɑːmɪt/
Definition 1 of 1
Pro Tip 1/3Space Phenomenon
A comet is a celestial event, not a regular occurrence, like a star or planet. 
The comet’s appearance was an extraordinary event that had astronomers excited.
Pro Tip 2/3Visible Tail
When near the sun, comets often have a visible tail, which distinguishes them from other space bodies. 
The comet’s tail stretched across the night sky, clearly visible from Earth.
Pro Tip 3/3Not a Star
Comets are sometimes confused with stars; remember, comets move and have tails. 
Although it looked like a star at first, the movement and tail revealed it was a comet.