The scale of the solar system is often difficult to grasp, with planets varying dramatically in size from small, rocky worlds to enormous gas giants. Earth is defined by its solid, dense surface, while Jupiter, the largest planet, is a colossal sphere of swirling gas and liquid. Comparing these two celestial bodies highlights the vast differences in planetary structure. To understand Jupiter’s true immensity, one must ask: how many Earths could fit inside its volume?
The Exact Volume Comparison
The direct, numerical answer is approximately 1,321 Earths. This figure is calculated by comparing the total volume of the two planets, treating both as near-perfect spheres. Since Jupiter is a gas giant, it lacks a solid, measurable surface like Earth.
Scientists define Jupiter’s “surface” at the 1-bar pressure level, which is the atmospheric pressure found at sea level on Earth. This point marks the boundary for defining the planet’s diameter and immense volume. While Jupiter’s diameter is about 11 times greater than Earth’s, the volume comparison is far more dramatic because volume scales with the cube of the radius.
What Makes Jupiter So Large
Jupiter’s enormous size is a direct consequence of its formation history, which began with the rapid accretion of vast amounts of gas and ice in the early solar system. The planet is primarily composed of the lightest elements, hydrogen and helium, a composition similar to that of the Sun. This abundance of light material allowed it to grow to a scale unmatched by any other planet.
Deep within the planet, internal pressure and temperature increase dramatically, compressing the hydrogen gas into layers of exotic matter. Beneath the visible atmosphere, hydrogen is squeezed into a liquid state, forming a massive “ocean” of liquid metallic hydrogen. This electrically conductive layer surrounds a central region that may contain a dense, rocky core of ice and heavier elements, though recent data suggest this core might be diffuse rather than solid.
Placing Jupiter in Solar System Context
The scale of Jupiter becomes even more apparent when placed among its planetary peers. Jupiter is so massive that it accounts for nearly two and a half times the mass of all the other planets, moons, asteroids, and comets in the solar system combined.
Saturn, the second-largest planet, is only about one-third the volume of Jupiter. Despite its size, Jupiter is still dwarfed by the Sun, the true giant of the solar system. The Sun’s diameter is roughly ten times that of Jupiter, meaning approximately 1,000 Jupiters could fit inside the Sun’s volume.
The Difference Between Size and Mass
Although Jupiter’s volume is equivalent to over 1,300 Earths, its total mass is only about 318 times that of Earth. This disparity between size and mass is explained by density, which is mass divided by volume. Since Jupiter is made overwhelmingly of hydrogen and helium, its average density is quite low, only 1.326 grams per cubic centimeter, about a quarter of Earth’s density.
The planet’s immense mass gives it a powerful gravitational influence throughout the solar system. Jupiter is credited with deflecting or capturing numerous comets and asteroids, potentially shielding the inner solar system from frequent impacts. Astronomers often use “Jupiter Mass” as a standard unit when describing the mass of newly discovered exoplanets.