Earth for Kids
Planet 3 from the Sun
Earth is the third planet from the Sun. Its day lasts 24 hours. Its year lasts 365 Earth days. That is from NASA's planetary fact sheet, checked 29 October 2026. A scale reads the same as on Earth. Read about it at three levels: Little, Middle and Big, and make your own Space Card.
Earth is our home. It has water, air, and a Moon. It is the only world we know that has living things.
Earth is the third planet from the Sun, just far enough for oceans of liquid water. A day is 24 hours, and a trip round the Sun takes about 365 and a quarter days, which is why we add a leap day every four years.
About seven tenths of Earth is covered in water, and its air keeps the average temperature near 15 degrees Celsius. It is the only place in the universe where life has been found so far.
From space, Earth looks blue because oceans cover most of it.
Earth in numbers
| Across | 12,756 km |
|---|---|
| From the Sun | 149.6 million km |
| A day | 24 hours |
| A year | 365 Earth days |
| Pull of gravity | the same as Earth |
| Average temperature | 15 °C |
| Moons | 1 |
Source: NASA planetary fact sheet, checked 29 October 2026.
How big is Earth?
Earth is 12,756 kilometers across, the same size as Earth. Earth is 150 million kilometers from the Sun, on average.
How hot or cold is Earth?
Earth averages 15 degrees Celsius, about a mild spring day.
Does Earth have moons?
Earth has 1 moon by NASA's count, and the number can grow as telescopes find more.
Can I see Earth tonight?
You're standing on it. Look down, then look up: everything else on this page is out there. Sky Tonight gives your own times from a ZIP.
How much would I weigh on Earth?
A child who weighs 80 pounds on Earth would read 80 pounds on Earth. That is a game number: it only shows how hard Earth pulls compared with Earth. Make your own Space Card to guess first and see all eleven worlds.