Jonathan McDowell has been tracking every object in orbit since 1989 — a one-person catalog that started as a weekly email newsletter and became the source governments and newsrooms cite when they nee

Key Points:

• Jonathan McDowell, an astronomer, has maintained a comprehensive, publicly accessible satellite catalog since 1989, which has become the primary reference for journalists, regulators, and satellite operators tracking objects in orbit, including SpaceX’s Starlink constellation.
• McDowell’s catalog uniquely distinguishes active satellites from inactive or decaying ones by manually cross-referencing U.S. Space Force tracking data with launch manifests and operator statements, providing detailed and up-to-date information not available in official government databases.
• In 2026, SpaceX launched 1,500 Starlink satellites in a single year, a pace that underscores the need for independent tracking; McDowell’s work enables accurate public and regulatory understanding of constellation growth and orbital congestion.
• The Starlink constellation supports a vast global broadband and direct-to-cellphone network, requiring a large number of satellites in multiple orbital shells to maintain continuous coverage, with plans for further expansion using SpaceX’s Starship launch system.
• McDowell’s privately maintained database serves as critical public infrastructure for space situational awareness, offering free and easily accessible data amid growing concerns from the astronomy community about satellite interference with observations and the increasing commercialization of space traffic data.