Earth size and scale context

Earth is the rocky planet on which we live and the most familiar anchor for planetary scale. It remains the only world known to host life, with long-lived surface oceans that have shaped both its geology and its atmosphere. Read its scale context, comparisons, and journey links on the canonical object page.

Scroll up for smaller

Scroll down for larger

Between the smallest and the largest, perspective is everything.

About

Scale of Space is a scroll-based journey through the universe, placing objects on a single logarithmic scale so you can compare size across an unbroken range.

Guides turn parts of that scale into curated essays, while focused views let you explore the same range through specific groups of objects.

Editorial

Solar System Planets From Electron to Atoms Stars To Scale Birth And Death Of Stars Black Holes To Scale

Views

Planets of the Solar System Stars of the Universe Black holes Subatomic scale

Return to Earth hello@scaleofspace.org

Between the smallest and the largest, perspective is everything.

About

Scale of Space is a scroll-based journey through the universe, placing objects on a single logarithmic scale so you can compare size across an unbroken range.

Guides turn parts of that scale into curated essays, while focused views let you explore the same range through specific groups of objects.

Editorial

Solar System Planets From Electron to Atoms Stars To Scale Birth And Death Of Stars Black Holes To Scale

Views

Planets of the Solar System Stars of the Universe Black holes Subatomic scale

Return to Earth hello@scaleofspace.org

Planets

Mars

Mars is the fourth planet from the Sun and the Solar System’s best-studied cold desert world. Ancient river valleys, lake beds, and minerals formed in water show that it once had a much wetter surface environment, even though today it is dry, thin-aired, and intensely cold.

Scale fact6,779 kmdiameter

Object class: Terrestrial planet
Mass: ~0.107 Earth masses
Host: Sun
Estimated age: ~4.5 billion years
Composition: Silicate rock, iron-rich minerals, polar ice
Temperature: ~210 K mean surface

Planets

Venus

Venus is the second planet from the Sun and the closest planetary match to Earth in size, but its surface conditions are radically different. A dense carbon-dioxide atmosphere drives a runaway greenhouse effect that makes Venus hotter than Mercury, even though it orbits farther from the Sun.

Scale fact12,104 kmdiameter

Object class: Terrestrial planet
Mass: ~0.815 Earth masses
Host: Sun
Estimated age: ~4.5 billion years
Composition: Silicate rock, iron core, dense carbon-dioxide atmosphere
Temperature: ~737 K mean surface