# Meteor shower

Also called: meteor, shooting star, radiant, ZHR, zenithal hourly rate.

A night with many shooting stars, when Earth passes through the dusty trail of a comet.

Meteors are grains of comet dust burning up 100 km overhead. In a shower they all seem to fly out from one point, the radiant (the Perseids from Perseus, the Geminids from Gemini). The ZHR — zenithal hourly rate — is how many you'd see per hour in a perfectly dark sky with the radiant overhead; real counts are lower, especially with moonlight or a low radiant.

**At the eyepiece:** No telescope needed: lie back somewhere dark, look about halfway up the sky (not at the radiant), and give it an hour. After midnight is usually best.

**In AstroPilot:** Tonight's “Coming up” lists meteor-shower peaks with the radiant's height for your location and how much the Moon interferes.

**Related:** [Comet](https://astropilot.space/glossary/comet.md), [Dark adaptation](https://astropilot.space/glossary/dark-adaptation.md), [Moonlight](https://astropilot.space/glossary/moonlight.md)

From the AstroPilot astronomy glossary: https://astropilot.space/glossary/meteor-shower