Minute and second of arc

What Are Minutes and Seconds of Arc?

Minutes and seconds of arc are tiny ways to measure angles. An arcminute is a very small angle, equal to 1/60 of a degree. An arcsecond is even smaller, equal to 1/60 of an arcminute, or 1/3600 of a degree. These tiny measurements help us see and understand the world around us.

Why Do We Use Them?

People have used these tiny angle measurements for a long time. Long ago, sailors used them to find their way across the oceans by looking at the stars. Today, scientists use arcseconds to study stars and planets in astronomy. These measurements help us know exactly where things are, both in the sky and on Earth.

Fun Facts

• The Moon looks about 31 arcminutes wide in the night sky.
• With good eyesight, you can see details that are about one arcminute apart.
• Arcseconds help scientists measure very small changes in the positions of stars.

These tiny measurements show us how careful and exact we can be when we study the universe!