SATELLITES

Satellites

Where the satellites whose pictures anyone can see are right now, and what they last saw. Gold ones hang over one spot on the equator and watch a whole face of the Earth. Blue ones cross the poles and see a strip at a time.

Controls

hold `W` `A` `S` `D` or drag	turn
hold `Q` `E`	roll
wheel, pinch, `+` `−`	zoom
click, `[` `]`	pick a satellite
`,` `.`	slower or faster time
`Space`	pause time
`N`	back to now
`T`	true scale
`L`	lights
`I`	this panel
`Esc`	let go of a satellite

Orbits

Geostationary. 35,786 km up, one lap a day, the same way the Earth turns, so each stays over one point. Turn time up and the Earth carries them round.
Sun-synchronous. 700 to 830 km up, about 100 minutes a lap, over the poles. The Earth's bulge swings the orbit round once a year, so each crosses the equator at the same local time every day.
Scale. At true scale geostationary is 6.6 Earth radii out and the polar orbits hug the surface. The default squeezes height on a log so both show.

Math

Orbits come from CelesTrak's mean elements, two-body motion solved with Kepler's equation plus the drift the Earth's bulge gives the orbit plane and perigee. Within about 50 km of SGP4 (Vallado et al. 2006) over three days, checked against satellite.js.
The Earth turns by Greenwich mean sidereal time. Heights are above the WGS 84 ellipsoid. The Sun's direction is the Astronomical Almanac's low-precision formula.
The globe is ray-cast per pixel at a lower resolution. Each pixel turns back into a latitude and longitude, looks up land or sea, and is lit by the Sun, which draws the terminator.
The view is one quaternion, steered the way Shapes is.

Credits

Orbital elements from CelesTrak. Land from Natural Earth.

Full disks from NOAA STAR (GOES), NICT (Himawari), and CIRA SLIDER (Meteosat, GK-2A). Daily true color below the polar imagers from NASA Worldview through GIBS. The rest link to MOSDAC, LandsatLook, and the Copernicus Browser.

Source. Public domain (CC0-1.0).

AI disclosure

Inspired by latest-earth, written 2022. Built on October 26th 2026 with Claude Code (Opus 5.5).