Observable Universe Horizon 3D Explorer vs Expanding Universe 3D Explorer
freetoolonline.com editorial teamBoth pages render real cosmology in one page load - 0 MB installed, USD 0, no account. The Observable Universe Horizon 3D Explorer covers the RESULTING horizon geometry; the Expanding Universe 3D Explorer covers the Hubble Law recession-speed relationship that produces it.
The numbers side by side
| Aspect | Observable Universe Horizon Explorer | Expanding Universe Explorer |
|---|---|---|
| Install size | 0 MB - runs in the browser | 0 MB - runs in the browser |
| Price | USD 0 | USD 0 |
| Core figure shown | 46.5 Gly comoving horizon radius vs 13.8 Gly light-travel guess | H0 about 67.4-73.5 km/s/Mpc, the Hubble tension |
| Main control | Cosmic-time slider growing two comparison spheres | Time animation of a uniformly stretching galaxy-marker grid |
| Reference shells | Milky Way, Local Group, Virgo galaxy cluster, Laniakea, Hubble radius, particle horizon | Near and far sample galaxy markers with live recession speed |
| Teaches | Why the horizon distance exceeds the naive light-travel distance | Why recession speed is proportional to distance (v = H0 d) |
Where the Expanding Universe Explorer wins
The Expanding Universe Explorer wins when the question is the mechanism itself - how recession speed scales with distance, and what the Hubble tension between early- and late-universe H0 measurements means.
Where the Horizon Explorer wins
The Horizon Explorer wins when the question is the resulting geometry - why the observable universe's real edge is 46.5 billion light-years away rather than the 13.8 billion light-years its age alone would suggest, and how that compares on one log scale to the Milky Way, Local Group, and Hubble radius.
A reasonable rule
As a reasonable rule, use the Expanding Universe Explorer first to see why space stretches and recession speed grows with distance, then use the Horizon Explorer to see how that stretching adds up over 13.8 billion years into a 46.5 billion light-year horizon.
See how to use the Observable Universe Horizon 3D Explorer for a step-by-step walkthrough.
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