WorkybooksEarth DayHow Does a Planet Differ From a Star?
How Does a Planet Differ From a Star?

Hello there, young explorers of the universe! Today, I’m thrilled to take you on an exciting journey through space to discover the fascinating differences between stars and planets. You see many tiny, twinkling lights, right? Some of those lights are stars, and some could be planets. Our plant & star might look similar from far away, but they are actually very different! First things first, what exactly differ between stars and planets? 

What is a Star?

A star is a giant ball of hot, glowing gas. Imagine a huge light bulb in the sky. Our Sun is a star! Stars shine brightly because they are extremely hot. They produce their own light and heat through a process called nuclear fusion, which happens deep inside them.

Fun Fact: The Sun is so big that you could fit about 1.3 million Earths inside it!

What is a Planet?

A planet is a large, round object that orbits or goes around, a star. Planets do not make their own light. Instead, they reflect the light of their star. For example, Earth is a planet that orbits the Sun. Planets can be made of rock, metal, gas, or a mix of these.

Fun Fact: There are eight planets in our solar system: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.

solar system with 8 planets

What is the Difference Between a Planet and a Star?

Let’s compare stars and planets side by side:

SizeThe stars are really big.
Example: If the Sun were the size of a basketball, the Earth would be about the size of a tiny pea!
The stars are super hot.
TemperatureThe stars are really big.Planets have a wide range of temperatures.
Example: Mercury can reach 800°F (430°C) during the day, while Neptune averages -353°F (-214°C).
CompositionThe stars are super hot.It can be made of rock, gas, or ice.
Example: Earth is made of rock and metal, while Jupiter is a giant ball of gas.
LightProduce their own light and heat through nuclear fusion.Reflect the light from their star; they don’t create their own light.
MovementStars stay in one place relative to us and form patterns in the sky called constellations.
Example: The Big Dipper is a constellation made of stars that always looks the same.
Planets move around stars in paths called orbits, changing position from night to night.
Example: Mars moves across the sky and is sometimes visible near other planets or stars.

Fun Fact: Did you know that our Sun is just one of the billions of stars in our galaxy, the Milky Way? And astronomers estimate that there are billions of galaxies in the universe, each containing countless stars and planets!

starry sky

Are all stars equally bright? 

No, stars can be different in brightness. Some stars look brighter because they are closer to us, while others are naturally brighter because they are bigger or hotter.

Are all stars the same color? 

No, stars can be different colors. Hot stars are blue or white, medium-temperature stars are yellow (like our Sun), and cooler stars are red or orange.

Sirius: The brightest star in the night sky. It’s very bright because it is close to us and very luminous
Betelgeuse:A red star that is cooler than many other stars. It’s part of the constellation Orion.
Rigel: A blue star in the constellation Orion. It is much hotter than Betelgeuse.

Colors of Stars: Remember, the color of a star depends on its temperature

Hot stars are blue or white.
Medium-temperature stars are yellow, like our Sun.
Cooler stars are red or orange.

Example: If you look at a flame, the hottest part is blue, and the cooler part is orange or red.


Neha Goel Tripathi, PhD

Accomplished sustainability educationist with over 20 years of experience in city planning, architecture and teaching. Experienced in research and consultancy on various projects covering climate change, sustainability, eco-sensitive zones, and smart cities. Passionate educator currently working on innovating climate change curriculum for K-12 students. I am driven to nurture students' critical thinking and awareness on environmental sustainability.

Leave a Reply

Your email address will not be published. Required fields are marked *