Europa, one of the major moons of the solar system Solar System The Moons of the Solar System From volcanic Io to ocean-world Europa, explore the moons of the solar system — the most fascinating worlds you can chase with a backyard telescope.
The Sun imaged in extreme ultraviolet by NASA's Solar Dynamics Observatory Solar System The Sun: Our Star Explained The Sun is a 4.6-billion-year-old ball of plasma anchoring the solar system. How our star works — its layers, sunspots, the solar cycle, and safe viewing.
Mercury, the smallest planet, in enhanced colour from MESSENGER Planets Mercury: The Smallest Planet Mercury is the smallest planet and closest to the Sun. Learn Mercury's extremes of heat and cold, its cratered surface, and how to spot it from your backyard.
Mars, the red planet, imaged by the Hubble Space Telescope Planets Mars: The Red Planet Mars is the red planet backyard astronomers chase hardest. Learn about Mars, its oppositions, polar caps and surface detail — and how to observe it.
The full Moon showing its craters and dark maria Solar System The Moon: Our Nearest Neighbour in Space The Moon is Earth's only natural satellite and the best first target for any telescope. Explore its phases, seas and craters, and how to observe the Moon.
A comet imaged against the stars by the Hubble Space Telescope Solar System Comets: What They Are and How to Photograph Them Comets are icy wanderers that grow glowing heads and tails as they near the Sun. Learn what comets are, where they come from, and how to photograph them.
Asteroid Vesta, one of the largest bodies in the asteroid belt Solar System Asteroids and the Asteroid Belt Asteroids are rocky leftovers from the solar system's birth, most orbiting in the asteroid belt. Learn what asteroids are, their types, and why they matter.
Pluto, the largest trans-Neptunian object in the Kuiper Belt Solar System Trans-Neptunian Objects and the Kuiper Belt Trans-Neptunian objects are icy worlds beyond Neptune in the Kuiper Belt. A guide to TNOs, dwarf planets like Pluto and Eris, and the outer solar system.
Planets of the solar system montage Solar System The Planets of the Solar System: A Complete Guide The eight planets of the solar system, from Mercury to Neptune — explored one by one with key facts, sizes, moons, and how to see each from Earth.
solar-system-dwarf-planet-pluto Solar System Pluto: Why It's No Longer a Planet — and Everything Else to Know Is Pluto a planet? No — it's a dwarf planet. Learn why Pluto was reclassified in 2006, what New Horizons revealed, and everything else to know about Pluto.
dwarf-ceres-globe Solar System Dwarf Planets: The Complete Guide to the Solar System's In-Between Worlds Dwarf planets are the solar system's in-between worlds — Pluto, Eris, Ceres, Haumea and Makemake. A complete guide to what they are and how they differ.
solar-system-hero Solar System The Solar System: A Complete Guide to Everything Orbiting the Sun A complete guide to the solar system — the Sun, eight planets, moons, dwarf planets, asteroids and comets — and everything else orbiting our star.
