ZenithTrack is a live, client-side sky viewer fixed to the point directly overhead (the zenith). Our purpose is to make Earth's rotation feel visible: the viewport is fixed - the motion is not by panning or time lapse, but provided by the Earth's actual live rotation. This requires a zoom level extreme enough to make the earth's live motion visible. The more you zoom in, the bigger things get, and the faster they move. To reveal motion - we use our (virtual) telescope as an "Angular Velocity Amplifier" showing a tiny sliver of the sky drift visibly - and genuinely - in real time.
Live page:
Further technical discussion:
This browser-based implementation includes:
- Real-time zenith RA/Dec tracking from user location + UTC
- Pan-STARRS imagery tiles (client-fetched and client-processed)
- SIMBAD object labels and curated "highlight" objects
- A minimal HUD and information panel
- Diagnostic tools for development/testing
app/- application source (HTML/CSS/JS)ZenithTrack design.md- design/architecture notes
Use a local HTTP server from the repository root:
python3 -m http.server 8080Open:
http://localhost:8080/app/
Notes:
- Geolocation behavior depends on browser policy. Depending on browser settings, some users may not even see a request to share their location before the browser rejects it.
- If geolocation is unavailable, ZenithTrack falls back to a default location (Stonehenge).
Public-facing controls:
fullscreen
Developer diagnostics:
freeze(development-only)Zoombutton (jumps simulated time to 30 seconds before the next highlight)
From browser devtools console:
window.zenithTrack.setTimeOffsetMinutes(240)
window.zenithTrack.getTimeOffsetMinutes()This lets you jump simulated time without restarting the app.
- Pan-STARRS image cutouts via STScI endpoints
- SIMBAD TAP/ADQL queries for objects/highlights
MIT. See LICENSE.