Definition

A flat map that shows the stars and constellations in the sky, often used in astronomy to help identify celestial objects at a specific time and location.

Example

The astronomer used a planisphere to locate the constellations visible that night.

Conversation

Have you ever used a planisphere to find constellations?

No, I haven't! How does it work?

It's really cool; you adjust it to your location and time to see what stars are visible.

That sounds fun! I should get one for stargazing.

Synonyms & Antonyms

Root Explanation

Planisphere → It is formed from "planus" (meaning flat) and "sphaera" (meaning sphere). The word describes a flat representation of the celestial sphere, typically used in astronomy.

Memory Tip

Think of a 'flat' ('planus') map of the 'sphere' ('sphaera') of stars and constellations — that's what a planisphere is.

Visually Confused Words