Scale of the Observable Universe
Every step outward increases scale by orders of magnitude. This journey moves from Earth, through the Solar System and nearest stars, out to the Milky Way, the Local Group, the cosmic web and finally the observable universe — which is far larger than the age of the universe times the speed of light.
Key takeaways
- The Milky Way is about 100,000 light-years across.
- The nearest large galaxy, Andromeda, is roughly 2.5 million light-years away.
- The observable universe is about 93 billion light-years in diameter.
- The whole universe may be much larger — the observable region is only what light has had time to reach us from.
About this visual
Each step outward in this journey multiplies distance by roughly a factor of a thousand. That is how our small planet becomes almost nothing on the map of the observable universe.
From Earth to the Solar System
Earth is about 12,742 km in diameter. The Moon orbits at 384,000 km. Neptune sits about 30 AU (roughly 4.5 billion km) from the Sun. The Oort Cloud may reach 100,000 AU.
Nearby stars and the Milky Way
Beyond the Solar System, distances jump to light-years — one light-year is roughly 9.5 trillion km. Proxima Centauri, the nearest star, is 4.24 light-years away. Our Milky Way is a barred spiral galaxy about 100,000 light-years across.
Beyond our galaxy
The Local Group of galaxies — Milky Way, Andromeda, and dozens of smaller members — spans about 10 million light-years. Zooming out further reveals the cosmic web of galaxy filaments and voids, hundreds of millions of light-years across. Read our companion pieces on galaxy clusters.
The observable universe
The observable universe is about 93 billion light-years in diameter. That may sound impossible for a universe that is only 13.8 billion years old, but the space between us and distant galaxies has been expanding while the light travelled. The observable region is the part we can, in principle, see. The whole cosmos may be much larger — we simply cannot say how much.
Related infographics
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Distance of the Planets from the Sun
See each planet's average orbital distance in astronomical units and understand why most Solar System diagrams are not to scale.
Stars
Life Cycle of a Star
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Black Holes
Anatomy of a Black Hole
The event horizon, singularity, accretion disk, photon region, corona and relativistic jets — what each region is and is not.
Read more on Universe & Planets
Sources and methodology
Values verified against official mission and archive pages on the updated date shown above. Numeric quantities are cited to the precision typical of introductory astronomy references.