The ISS Tracker follows the International Space Station in real time in its race around the world, following its orbit and pointing its position in the sky at all times. A project inspired by my fascination with space, which has always stimulated the humankind’s imagination. A tribute to the technical prowess that is the ISS, and to the astronauts on board.

The International Space Station takes around 92 minutes to circle the Earth. The ISS Tracker uses two-line orbital parameters, or TLE (for Two-Line Elements), to determine the orbit of the station and calculate its position. The azimuth and elevation are then calculated relative to the GPS coordinates of the observer, the date and time, in order to define the direction to point. The position of the ISS is recalculated every 10 seconds and the direction pointed by the hand of the ISS Tracker is updated.

Technically, the ISS Tracker is based on an Arduino Uno, a CNC shield, an RTC module, two Nema stepper motors. The position of the ISS, the azimuth and the elevation are calculated directly by the Arduino, thanks to the excellent ArduinoP13 library by Thorsten Godau, based on the Plan 13 algorithm of James Miller, used to determine the position of the satellites around the Earth.