Scale Comparison

Earth vs the Sun, to scale

The Solar System is often taught through the variety of its planets, but the moment the Sun enters the frame the hierarchy becomes unmistakable: the planets stop looking like the main cast and start looking like byproducts around one overwhelmingly dominant star.

Shared physical scale
775,209km
Earth12,742 km
Sun1.39 million km

Scale insight

The Sun's diameter is about 109 times Earth's.

Earth is the world we inhabit, so it easily becomes the emotional center of any planetary picture. Physical scale says something harsher and more interesting. Earth is one small rocky world orbiting a star that contains almost all of the Solar System’s mass.

That contrast is exactly why star-planet comparisons are so clarifying. They do not merely tell you that stars are bigger. They show that the whole system is organized around an object whose scale changes the meaning of every planet around it.

Objects

Open each object in context

Planets

Earth

12,742 kmdiameter

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.

Object class
Terrestrial planet
Composition
Silicate rock and iron core
Temperature
~288 K mean surface
Estimated age
~4.54 billion years
Host
Sun
Visual creditNASA / Apollo 17 crew / Public domainSource: Wikimedia Commons
Stars

Sun

1.39 million kmdiameter

The Sun is the star at the center of the Solar System and the engine behind every climate and orbit within it. It fuses about 600 million metric tons of hydrogen each second, while photons created in the core can take roughly 250,000 years to work their way to the visible surface.

Object class
G-type main-sequence star
Mass
~333,000 Earth masses
Temperature
5,772 K surface
Estimated age
~4.6 billion years
Composition
Hydrogen and helium
Visual creditThomas Bresson from Belfort, France / CC BY 2.0Source: Wikimedia Commons

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.

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