How to Use the Observable Universe Horizon 3D Explorer - Step by Step
Open the Observable Universe Horizon 3D Explorer, drag the "Cosmic time" slider from the Big Bang toward today, and watch the two growing spheres pull apart.
Scrub cosmic time
Drag the "Cosmic time" slider to jump to any moment between the Big Bang and today (13.787 billion years), or press "Play cosmic time" to move automatically. Watch the orange comoving-horizon sphere outrun the green light-travel-distance sphere as time advances.
Switch between comoving and light-travel readings
Press "Showing: comoving distance" to flip the facts-panel headline to "Showing: light-travel distance" for the identical cosmic moment - the two numbers describe the same instant differently, not two different moments.
Pick a reference shell
Press "Milky Way", "Local Group", "Virgo galaxy cluster", "Laniakea Supercluster", "Hubble radius", or "Particle horizon" to load that shell's real characteristic distance and fact text into the panel and highlight it in the scene.
Read the facts panel
The always-visible table lists the age of the universe, the 46.5 billion light-year comoving horizon radius, the 13.8 billion light-year naive light-travel distance, the 14.4 billion light-year Hubble radius, and two competing published galaxy-count estimates.
Drag to orbit and use fullscreen
Drag to orbit the camera, scroll or pinch to zoom, and use the Fullscreen button to expand the whole wrapper for a clearer view.
Next: see when to use this explorer or how it compares to the Expanding Universe 3D Explorer.
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