Radiant
The point in the sky that all the meteors in a shower seem to fly out from.
During a meteor shower, if you trace each shooting star backwards, the lines all seem to meet at one spot. That spot is called the radiant. The meteors don't really come from that point. The dust grains are actually travelling side by side, like rain falling in parallel lines. Because we see them in perspective, they seem to spread out from a single point, just as long straight railway tracks look as if they spread out from a single far-off spot.
The radiant is how meteor showers get their names. The Perseids seem to start in the constellation Perseus, the Leonids in Leo and the Geminids in Gemini. Knowing where the radiant is helps you tell whether a meteor belongs to a shower or is just a random one.
A useful tip: don't stare straight at the radiant. Meteors near it look short, while those further away draw longer, more beautiful streaks. Also, the higher the radiant climbs in the sky, the more meteors you will see, which is why many showers are best after midnight. You don't need any equipment; just a star map or app to find the right constellation.
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Level: Beginner Ages 7 and up