Olbers' Paradox 3D Explorer vs Expanding Universe 3D Explorer
freetoolonline.com editorial team
Both pages teach a real cosmology figure in one page load - 0 MB installed, USD 0, no account. The Olbers' Paradox 3D Explorer uses a finite universe age and cosmic expansion together to answer one specific question, why the night sky is dark; the Expanding Universe 3D Explorer visualizes the mechanics of that expansion itself, independent of the paradox question.
The numbers side by side
| Aspect | Olbers' Paradox Explorer | Expanding Universe Explorer |
|---|---|---|
| Install size | 0 MB - runs in the browser | 0 MB - runs in the browser |
| Price | USD 0 | USD 0 |
| Key figure | Universe age: 13.8 billion years (Planck 2018) | Hubble Law: v = H0 d, H0 in the 67.4 to 73.5 km/s/Mpc tension range |
| What it varies | Model (naive vs real) and shell count (1 to 12, capped at 6 in real mode) | Time, across a uniformly stretching galaxy-marker grid |
| What it answers | Why the night sky is dark instead of blazing bright | Why farther galaxy markers recede faster |
| History cited | Kepler 1610, Olbers 1823, Poe 1848, Kelvin 1901 | Modern H0 tension between early- and late-universe measurements |
Where the Olbers' Paradox Explorer wins
The Olbers' Paradox Explorer wins when the question is specifically why the night sky is dark - it is the only page on the site that puts the naive infinite-static model side by side with the real finite-age model to answer that exact puzzle, with the historical dates attached.
Where the Expanding Universe Explorer wins
The Expanding Universe Explorer wins when the question is the expansion mechanism itself - it time-scrubs a stretching galaxy grid directly, which the paradox explorer does not show at all.
A reasonable rule
As a reasonable rule, use the Olbers' Paradox Explorer first to understand why the dark night sky itself is a real puzzle with a real history, then use the Expanding Universe Explorer to see the stretching-space mechanism that is part of the modern answer.
See how to use the Olbers' Paradox 3D Explorer for a step-by-step walkthrough.
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