Explore why a meteor shower's streaks seem to radiate from one point. Compare the Perseids and Leonids, with the Perseids peaking around Aug 12-13 at ZHR ~100 under ideal skies.
Published literacy figures: Perseids peak Aug 12-13, ZHR ~100 under ideal skies, and parent comet 109P/Swift-Tuttle. The Leonids come from 55P/Tempel-Tuttle.
Drag to orbit and scroll or pinch to zoom. Switch showers, scrub streak speed, or lengthen the trail to see how perspective keeps the radiant fixed.
Meteor Shower Radiant 3D Explorer
freetoolonline.com editorial teamThis browser explorer shows a meteor shower radiant: meteors in one stream travel on nearly parallel paths, but perspective makes them appear to radiate from one sky point. The page compares the Perseids and Leonids.
Switch showers, scrub speed, and lengthen the streaks. Earth 3D Globe owns the planet view; this page owns the sky-geometry explanation for why a radiant appears.
- Perseids and Leonids toggle
- Parallel meteoroid streaks on a local sky dome
- Radiant marker showing the apparent source point
- Trail-length and speed scrubbers with play/pause
- Perseids peak Aug 12-13, ZHR ~100, parent 109P/Swift-Tuttle
- Leonids parent 55P/Tempel-Tuttle
- Runs fully in the browser with the vendored three.js engine - no account, no upload
Students see perspective geometry instead of magic; teachers contrast shower names and parent comets; curious readers learn why sky streaks look like spokes.
| Figure | Value | Source note |
|---|---|---|
| Perseids peak | Aug 12-13 | Typical annual maximum |
| Perseids ZHR | ~100 | Ideal dark-sky zenithal hourly rate |
| Perseid parent | 109P/Swift-Tuttle | Dust stream source |
| Leonid parent | 55P/Tempel-Tuttle | Contrast shower |
Walking the controls, move by move
Five moves cover the whole scene. Run them in order and the radiant marker, the streak geometry, and the parent-comet contrast each land on their own.
- Open the explorer and wait for the local sky dome and the radiant marker to paint.
- Read the facts panel: Perseids peak Aug 12-13, ZHR ~100, parent 109P/Swift-Tuttle.
- Set Shower to Leonids to swap the parent stream to 55P/Tempel-Tuttle, then back to Perseids.
- Scrub Speed and Trail, and press Pause streaks to freeze the sky mid-flight.
- Drag to orbit and scroll or pinch to zoom - from a new angle the streaks still point back to the same marker, which is what proves the radiant is a direction rather than a place. Press Fullscreen for a projector.
How this explorer compares with the sibling scenes
The Meteor Shower Radiant 3D Explorer teaches radiant perspective. Earth 3D Globe teaches the planet; Three-Body Problem 3D teaches gravitational choreography.
| Option | Strength | Access | Trade-off |
|---|---|---|---|
| Meteor Shower Radiant 3D (this page) | Perseids/Leonids radiant geometry | Free, in browser, USD 0, 0 MB to install | Teaching scene, not a forecast |
| Earth 3D Globe sibling | Planet-scale orientation | Free web | No meteor-radiant perspective |
| Three-Body Problem 3D sibling | Classical gravity sandbox | Free web | Different topic entirely |
Where the scene stops
Everything renders on your device with WebGL. The 3D engine loads once (about 0.7 MB) and is cached; no scene data is sent to a server.
This is an educational perspective-geometry sky scene - not a real-time meteor forecast or orbit integrator. For tonight's cloud cover, moonlight, or local visibility window, use a live observing app instead.
When you need session fit and limits, see when to use Meteor Shower Radiant 3D Explorer. The Space 3D collection also includes Earth 3D Globe and Three-Body Problem 3D.
Frequently Asked Questions
What does the Meteor Shower Radiant 3D Explorer show?
A local sky dome where nearly parallel meteoroid paths appear to radiate from one point because of perspective. You can switch between the Perseids and Leonids.
Why do parallel meteors seem to come from one point?
For the same reason railroad tracks appear to meet in the distance: perspective compresses parallel lines toward a vanishing point on the sky.
What are the key Perseids figures here?
The page uses a typical Perseids peak of Aug 12-13, ZHR around 100 in ideal conditions, and parent comet 109P/Swift-Tuttle.
What are the Leonids used for?
The Leonids provide a second parent stream - 55P/Tempel-Tuttle - so the same radiant logic can be compared with a different shower label.
Is this a live sky forecast?
No. It is an educational radiant explainer - not a real-time meteor forecast, weather model, or orbit simulator.
Does the radiant mean meteors start there?
No. The radiant is the apparent source direction on the sky, not the physical starting point of the meteors.