Planets

Inner Planets

The inner, rocky planets of our solar system are Mercury, Venus, Earth, and Mars.

Outer Planets

The outer planets include the gas giants Jupiter and Saturn, and the ice giants Uranus and Neptune.

Planet vs. Dwarf Planet

Planets have cleared their orbital path of similar objects, whereas dwarf planets have not.

Venus

The hottest planet in the solar system, featuring a slow backward spin and a runaway greenhouse effect.

Earth

Our home planet, and the only known world with liquid water (covering 70% of the surface) and living things.

Mars

A dusty, cold desert world with a thin atmosphere, polar ice caps, canyons, and extinct volcanoes.

Mars Habitability Factors

Soil with extractable water, moderate temperatures, sufficient sunlight for solar panels, and 38% Earth gravity.

Mercury Temperatures

Reaches up to 430°C on the sun-facing side and -180°C on the dark side.

Jupiter

More than twice as massive as all other planets combined, featuring the Great Red Spot storm.

Saturn

A gas giant adorned with a dazzling, complex ring system.

Uranus

Discovered in 1781 by William Herschel; notable for its 97.77-degree tilt causing it to spin on its side.

Neptune

The eighth major planet, characterized by its dark, cold environment and supersonic winds.

Dwarf Planets Examples

Ceres, Pluto, Makemake, Haumea, and Eris.

Pluto

A complex dwarf planet in the Kuiper Belt with ice mountains, a massive heart-shaped glacier, and five moons.

HD 260655 b and c

Super-Earth planets discovered in 2022 that are too hot to support life.

Earth's Atmosphere

Gaseous layer composed of 78% nitrogen, 21% oxygen, and 1% other gases that regulates climate and shields solar radiation.

Hydrosphere

All water on Earth in liquid, gaseous, and solid phases, including oceans, ice sheets, and groundwater.

Biosphere

The global sum of all living organisms, closely interacting with the atmosphere, hydrosphere, and geosphere.

Geosphere

The solid part of the planet composed of rock and minerals, including the crust, mantle, core, and soil layer.