Planets & Moons
There are 8 officially recognized Solar System planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. Most of them, except Mercury and Venus, have their own natural satellites, commonly called “moons.” Some of the dwarf planets, like Pluto and Eris, have moons, too. Here, you’ll learn the best dates to observe planets in the sky and find everything you need to know about planets, dwarf planets, and natural satellites. When you learn enough, test your astronomy skills with our challenging quizzes!

Jupiter Facts: The Biggest Planet in the Solar System
The bright Jupiter is known for its many moons, unstable surface, and mysterious Great Red Spot. Is there something else? Find out!

Stars Versus Planets: What’s the Difference
Learn 5 easy ways to tell stars from planets in the sky and find fundamental differences between these space objects.

The Brightest Deep Sky Objects in June 2023
This June, observe faraway star clusters and see the Moon and planets meeting deep-sky objects! Read on not to miss the beauty. 🌌

Planetary Alignment 2023: Saturn, Neptune, Jupiter, Mercury & Uranus Visible Tonight
What is a planet alignment, and when to see the next one in June 2023? Check out this article to ensure you do not miss the moment when the planets line up in the sky.

June 2023: What Planet is Next to the Moon?
What is that bright dot shining near the Moon tonight? Find out about stars and planets that can be seen next to our natural satellite this month!

Facts About Venus: Explore the Earth's Sister Planet
Why is Venus so hot and bright? When is the best time to observe it? Read this article to get answers to these and many other questions about this planet.

Fun Facts About Venus — the Earth’s Evil Twin
How long is a day on Venus? Why is Venus hotter than Mercury? Take this quiz and test your knowledge about this mysterious planet that is both very like and very unlike the Earth.

Facts About Mercury: All You Need to Know
Explore the closest planet to the Sun! Find out how long a day on Mercury is and how many moons the planet has. Also, keep up with the upcoming Mercury events!

Mars: Facts About the Red Planet
Why is Mars red? What’s the gravity on Mars? Read this article to get answers to these and many other questions and learn more about the Red Planet.

Planet Saturn: Explore Saturn's Rings, Moons, and More
How many rings does Saturn have? Where is Saturn tonight in the sky? Find answers to these and other most common questions about Saturn in our article.