Sunspots

📖 In short

Sunspots are dark patches that appear on the Sun's glowing surface. They look dark because they're a little cooler than the rest of the surface, but they're still very hot! Some are enormous, several times bigger than the Earth.

🤩 Did you know?

A sunspot is about 4000 degrees, and the area around it about 6000 degrees.
A big sunspot can be 32 thousand kilometers across.
Sunspots usually appear between 5 and 15 degrees north and south of the Sun's equator.
The magnetic field in a sunspot is thousands of times stronger than normal.

🔎 Find out more

🌟 Magnetic spots

Sunspots form where very strong magnetic forces stop some of the heat from inside the Sun reaching the surface, so those places cool a little.

🔍 They move and change

Sunspots appear and vanish, and move across the Sun's face because the Sun spins. From their movement scientists learned that the Sun turns about once a month.

💡 The eleven-year cycle

The number of sunspots rises and falls in a cycle of about 11 years. When there are lots of spots, powerful explosions happen on the Sun, causing the polar lights on Earth.

🎯 Don't look yourself

Scientists watch sunspots with special telescopes and strong filters. You must never look at the Sun directly or through an ordinary telescope.

🧩 Test yourself

1 Why do sunspots look dark?

2 About how long is the sunspot cycle?

3 A big sunspot can be ?? thousand kilometers across.

4 Which picture shows “Sunspots”?

🪐 Discover more

📷 Picture sources: Wikimedia Commons

NASA Goddard Space Flight Center from Greenbelt, MD, USA · Public domain