A gas planet (or gas giant) is a huge planet made mostly of gases like hydrogen and helium, with no solid surface to stand on, and usually a small dense core deep inside.

Quick Scoop

What is a gas planet?

  • It is a giant planet made primarily of gas, especially hydrogen and helium.
  • Instead of a hard ground like Earth, it has thick, swirling atmospheric layers that just get denser as you go down.
  • Deep inside, there is probably a compact core of rock, metal, and/or ice surrounded by vast envelopes of gas and, at high pressure, weird “fluid” forms of hydrogen.

Gas planets in our solar system

  • The outer four planets are the classic examples: Jupiter, Saturn, Uranus, and Neptune.
  • You could not stand on them because there is no solid surface, only denser and denser gas and fluid as you go down.
  • They are much larger than the inner rocky planets (Mercury, Venus, Earth, Mars) and each has many moons.

In everyday space talk, “gas planet” and “gas giant” are often used for all four outer planets, but many astronomers now split them into “gas giants” (Jupiter, Saturn) and “ice giants” (Uranus, Neptune) because of differences in what they’re mostly made of.

Simple mental picture

Imagine a colossal, deep ocean of invisible air and exotic fluids wrapped around a tiny central pebble: that’s the basic idea of a gas planet, with clouds and storms raging through layer after layer instead of continents and oceans like Earth.

Information gathered from public forums or data available on the internet and portrayed here.