satellitetracking

Satellitetracking is the monitoring and prediction of the motion of artificial satellites. It involves collecting observations and applying orbital models to determine current positions and forecast future locations.

The practice combines data from ground- and space-based sensors with mathematical models to generate ephemerides, or predicted satellite coordinates, at specified times. Common methods include radar and radio tracking from ground stations, optical observations with telescopes, and laser ranging for selected satellites. Observations are processed to derive orbital elements and propagated using standard models such as SGP4/SDP4, often summarized as Two-Line Elements (TLEs) that are regularly updated to reflect maneuvers and perturbations.

Key data sources include the U.S. Space Surveillance Network, Space-Track, and publicly available catalogs such as Celestrak, along with national or international space agencies. These data underpin a range of applications, including satellite operations and mission planning, conjunction and collision-avoidance assessments, debris monitoring, and scientific research that requires precise positional information.

Accuracy and limitations are driven by several factors. Measurement errors, geometry of observations, and perturbations from atmospheric drag, Earth's oblateness, gravitational influences of the Moon and Sun, and solar radiation pressure all affect predictions. Predictive accuracy degrades over time without new observations or updates to the orbital elements, necessitating regular tracking and data refreshes.

Historically, satellitetracking emerged with early radar techniques in the 1950s and has evolved into integrated, international networks that support modern space activities and safety.