Radiant (meteor shower)

The radiant is the vanishing point of the meteor paths, which are parallel lines in three-dimensional space, as seen from the perspective of the observer, who views a two-dimensional projection against the sky.

Shower meteors may appear a short time before the radiant has risen in the observer's eastern sky.

During the active period of most showers, the radiant moves nearly one degree eastwards, parallel to the ecliptic, against the stellar background each day.

Meteor showers are mostly caused by the trails of dust and debris left in the wake of a comet.

As an exception, the Geminids are a shower caused by the object 3200 Phaethon,[2] which is thought to be a Palladian asteroid.