46 articles
Solar System
Planets, the Sun, moons, asteroids and how our cosmic neighborhood works.
Explore the night sky, one clear answer at a time
Clear, source-checked answers about planets, stars, galaxies and stargazing — from the color of the Moon to the distance of the nearest star.
Browse by topic
28 articles
Stars
Star types, brightness, the nearest stars and the light-years between them.
10 articles
Constellations
How to find Orion, Taurus, the Big Dipper and the patterns of the night sky.
12 articles
Galaxies
The Milky Way, Andromeda, nebulae and the scale of the universe.
5 articles
Moon
Phases, orbit, color and the eclipses our nearest neighbor produces.
11 articles
Stargazing
Telescopes, Stellarium and practical guides for observing the sky.
Latest articles
Solar System
Discovering the current location of Voyager in interstellar space
Learn about the current location of Voyager 1 and 2, their distances from Earth, and how they navigate the harsh environment of interstellar space.
Stargazing
Differentiating between refractor and reflector telescopes
Learn the key differences between refractor and reflector telescopes to choose the right optical design for planetary viewing or deep-sky observation.
Stars
How far away is the nearest star in light years?
Discover how far Proxima Centauri is from Earth and learn about its physical characteristics, planetary system, and distance measurements.
Solar System
How many natural satellites does the earth possess?
Explore Earth's celestial companions, from the permanent Moon to transient quasi-satellites and cosmic dust clouds located at Lagrange points.
Solar System
How many planets orbit the sun in second grade lessons
Learn how many planets orbit the sun and discover key facts about the eight official planets, from Mercury to Neptune, for students and educators.
Stargazing
A beginner's guide on how to use Stellarium
Learn how to use Stellarium to simulate the night sky, configure geographical coordinates, and optimize visual settings for celestial observation.