A star is a hot, glowing ball of gas. When you look up in the night sky, you can see countless twinkling stars. Can you see any stars during the daytime? Of course! The light of daytime comes from our closest star: the Sun.

Just how close is the Sun to Earth? Way, way closer than other stars, but still pretty far away. It’s approximately 93 million miles away from Earth. That’s 400 times farther than the distance between Earth and the Moon!

However, it’s a good thing that Earth isn’t too close to the Sun. If we were too close, it would be way too hot to live here. The Sun’s surface is very hot, and its atmosphere is even hotter. And the Sun’s core is the hottest part of all, at a sizzling 27 million degrees Fahrenheit!

Our Sun is about 100 times wider than Earth, but it is just an average sized star. Astronomers have found some stars that are 100 times bigger than the Sun and others that are 10 times smaller.

More fun facts about the Sun!

• The Sun goes through ups and downs in activity like solar flares. It gets more active with more sunspots and then less active over a period of 11 years. This is called the solar cycle.

• The Sun has been getting slowly brighter since it was born. A couple of billions of years ago, the Sun was a little dimmer than it is now.

• The Sun contains almost ALL of the material in our solar system. 99% of it. All the planets, asteroids and comets add up to less than 1% of the total.

• The Sun is so far away that it takes light about 8 minutes and 20 seconds for it to get to us – and light is the fastest thing in the universe.

Our home planet Earth is a rocky, terrestrial planet. It has a solid and active surface with mountains, valleys, canyons, plains and so much more. Earth is special because it is an ocean planet. Water covers 70% of Earth's surface.

Our atmosphere is made mostly of nitrogen and has plenty of oxygen for us to breathe. The atmosphere also protects us from incoming meteoroids, most of which break up in our atmosphere before they can strike the surface as meteorites.

Since we live here, you might think we know all there is to know about Earth. Not at all, actually! We have a lot we can learn about our home planet. Right now, there are many satellites orbiting Earth taking pictures and measurements. This is how we can learn more about weather, oceans, soil, climate change, and many other important topics.

Time on Earth

• A day on Earth lasts a little under 24 hours.

• One year on Earth lasts 365.25 days. That 0.25 extra means every four years we need to add one day to our calendar. We call it a leap day (in a leap year).

Earth’s Neighbors

• Earth has just one Moon. It is the only planet to have just one moon.

• Earth has lots of spacecraft watching it. There is still a lot we can learn about our home planet.

• Earth is the third planet from the Sun in our solar system. That means Venus and Mars are Earth’s neighboring planets.