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!

February 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!

Planet Uranus: The Coldest Planet
Uranus has a peculiar chemical composition, extreme temperatures, and the most unusual axial tilt. Here we’ll take a closer look at this planet.

What is a retrograde in astronomy? Retrograde meaning in simple words
Figure out how retrograde motion works and learn if you should dread Mercury retrograde.

Fun Planet Saturn Facts: 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.

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 Neptune: Explore the Farthest Planet From the Sun!
How big is Neptune? What is Neptune made of? Why is Neptune blue? Read our article and learn curious facts about the outermost planet in the Solar System.

Discover the Amazing Planet Venus
Venus is the second planet from the Sun and the brightest planet in our sky. Learn more facts about Venus and the best time to see it in the sky.

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!

Planets in Conjunction 2023: Venus Near Saturn, Neptune, Jupiter
Planets meet in the sky relatively infrequently. Check our planetary conjunctions list so as not to miss them!