Overhead Now
Every tracked, active satellite (about 16,000 objects) plotted live on a globe you can spin, plus what is above your horizon right now, a geostationary dish-angle test, and upcoming ISS passes for any point on Earth.
Built as a public rebuttal tool: same orbital data and same math as every satellite tracking site, so any number here can be checked against N2YO, Heavens-Above, or NASA's Spot the Station.
How it works
- Data: two-line element sets (TLEs) for the
active group from CelesTrak, which republishes the U.S. Space Force catalog. Bundled as tle.js with the snapshot timestamp in window.TLE_UPDATED.
- Propagation: SGP4 via satellite.js 7.1.0 (MIT), compiled to a single script in
satellite.js.
- Coastlines: simplified from johan/world.geo.json into
coast.js.
- Rendering: plain canvas 2D, no frameworks. Orthographic globe with drag-to-rotate, zoom, and pole/edge-on views; polar sky chart.
Run it
Open index.html in a browser. No server, no build step, no network needed.
Refresh the catalog
Positions drift a few km per day after the snapshot. To refresh:
curl -o active.tle "https://celestrak.org/NORAD/elements/gp.php?GROUP=active&FORMAT=tle"
python3 build_tle.py active.tle
build_tle.py rewrites tle.js. Commit and redeploy.
Deploy
Static files; drop the folder on Vercel, Netlify, or GitHub Pages.
Credits
Randy Barnhill, Barnhill Industrial Group. Built with Claude. Orbital elements courtesy of T.S. Kelso / CelesTrak.
