Help Shape the Future of Space Exploration

Join The Planetary Society Now  arrow.png

Join our eNewsletter for updates & action alerts

    Please leave this field empty
Explore

Compare the Planets

Comparing the physical characteristics of the worlds in our solar system (and beyond)

The worlds of our solar system come in all shapes, sizes, and colors. Red-eyed Jupiter, ringed Saturn, and frigid Uranus and Neptune are giant gassy globes containing nearly all of the matter in the solar system. These Jovian planets, or gas giants, are huge worlds of air, clouds, and fluid that may have no solid surfaces no matter how deep you go. Everything else in the solar system is just rock, ice, and dust. The largest rockballs are known as the terrestrial planets: Mercury, Venus, Earth, and Mars, with our Moon usually considered part of the club, and now Vesta is applying for membership. Earth is the biggest of all the rocky worlds.

But the planets are not the only worlds of the solar system. All but two of the planets are orbited by moons, each of them a world unto itself. The largest moons are bigger than the smallest planets, and 16 or 17 would qualify as dwarf planets if they orbited the Sun. There are more than 100 Kuiper belt dwarf planets, but only one among the asteroids, Ceres.

Six solid worlds -- Venus, Earth, Mars, Titan, Triton, and Pluto -- have atmospheres dense enough to produce weather. Eris likely does, when it is near its perihelion. We have witnessed active geology on four worlds -- Earth, Io, Enceladus, and Triton -- and we suspect it on Venus, Europa, and Titan. Comparing the same processes across many worlds helps us to understand how each planet's unique composition and history influence its present state, and will help us predict what to expect on Earth in the future.

Pretty Pictures with Many Worlds

Pioneer 10 departs Jupiter (and Io)

Pioneer 10 departs Jupiter (and Io)

This is a parting shot of Jupiter and Io, taken December 5, 1973, by the Pioneer 10 spacecraft, the first to see either world as a crescent.

Filed under Jupiter's moons, Io, pretty pictures, amateur image processing, Pioneer 10 and 11, global views, many worlds, Jupiter

Terra Cognita

Terra Cognita

Pushing back the frontiers of the unknown. On the left: destinations in the Solar System as seen by historic robotic spacecraft and telescopes. On the right: the same worlds as seen by recent missions that have filled in some of the blank spaces on the map. Click the image for the full-size version.

Filed under pretty pictures, many worlds, Mercury, the Moon, Mars, Titan, asteroids, asteroid 1 Ceres, asteroid 4 Vesta, Pluto, Mariner 10, MESSENGER, Soviet lunar missions, Lunar Reconnaissance Orbiter, NASA Mars missions before 1996, Mars Reconnaissance Orbiter, Voyager 1 and 2, Cassini, New Horizons, Dawn

Dunes on Earth and Titan

Dunes on Earth and Titan

Left: Dune interactions with topographic obstacles in Namibia as seen on Google Earth. Right: Cassini radar image of the Belet sand sea on Titan, obtained during T8, 300 m resolution.

Filed under Cassini, pretty pictures, Titan, scale comparisons, Saturn's moons, radar imaging

Items 55 - 57 of 100  Previous11121314151617181920Next

Section Highlights

Planetary Facts

Mass, diameter, density, gravity, orbital characteristics, presented both in metric units and measured relative to Earth.

More »

Asteroids and Comets Visited by Spacecraft

A comparison of all the asteroids and comets ever visited by spacecraft, up to date as of November 10 (when Deep Impact flew past Hartley 2). Vesta is not included.

More »

Every Round Object in the Solar System, to Scale

A correctly scaled, reasonably correctly colored view of the largest bodies in the solar system.

More »

Facebook Twitter Email RSS AddThis

JOIN THE
PLANETARY SOCIETY

Our Curiosity Knows No Bounds!

Become a member of The Planetary Society and together we will create the future of space exploration.

Join Us

LightSail - Flight by Light

Support LightSail!

LightSail-1 will attempt to demonstrate controlled solar sailing—flight by light—for CubeSats (tiny, low-cost satellites).

In 2016, The Planetary Society’s LightSail program will take the technology a step further.

I want to help!

Fly to an Asteroid!

Travel to Bennu on the OSIRIS-REx spacecraft!

Send your name

Join the New Millennium Committee

Let’s invent the future together!

Become a Member

Connect With Us

Facebook! Twitter! Google+ and more…
Continue the conversation with our online community!