Sun for Kids
A star
The Sun is our star, the center of the solar system. Its day lasts 25.4 Earth days. It has no year, because it does not go around the Sun. That is from NASA's planetary fact sheet, checked 29 October 2026. A scale there reads 27.9 times as much as on Earth. Read about it at three levels: Little, Middle and Big, and make your own Space Card.
The Sun is a big, hot ball of glowing gas. It gives us light and warmth every day. Never look right at the Sun.
The Sun is a star, the one our whole solar system goes around. It is so big that more than a million Earths could fit inside it. Its light takes a little over eight minutes to reach us.
The Sun holds more than 99 percent of all the mass in the solar system, so its pull keeps every planet in orbit. Its surface is about 5,500 degrees Celsius, and in its core, hydrogen joins into helium and gives off the energy that lights Earth.
The Sun spins too: about once every 25 days near its middle, slower near its poles.
Sun in numbers
| Across | 1,392,684 km |
|---|---|
| From the Sun | none: it is the center |
| A day | 25.4 Earth days |
| A year | none: the Sun has no year |
| Pull of gravity | 27.9 times Earth's |
| Average temperature | 5500 °C |
| Moons | none |
Source: NASA planetary fact sheet, checked 29 October 2026.
How big is Sun?
Sun is 1,392,684 kilometers across, 109 Earths wide. The Sun is the center, so there is no trip to count.
How hot or cold is Sun?
The Sun's surface is about 5,500 degrees Celsius, far hotter than any oven or fire.
Does Sun have moons?
The Sun has no moons. The planets go around it.
Can I see Sun tonight?
Never look at the Sun, not even with sunglasses. It is the one thing in the sky that can hurt your eyes. Sky Tonight gives your own times from a ZIP.
How much would I weigh on Sun?
A child who weighs 80 pounds on Earth would read 2232 pounds on Sun. That is a game number: it only shows how hard Sun pulls compared with Earth. Make your own Space Card to guess first and see all eleven worlds.
More worlds
Never look straight at the Sun. Sunglasses do not make it safe.