CP4

CP4 is an active satellite operated by United States, launched on 2007-04-17 from Baikonur, Kazakhstan. After 19 years in orbit, it continues to be tracked by global surveillance networks. It orbits in Low Earth Orbit (LEO) at altitudes between 622 km and 721 km with an inclination of 98.4°. It travels at approximately 27,084 km/h (7.52 km/s), completing one full orbit every 98 minutes — that’s roughly 14.67 orbits per day. Its near-polar, sun-synchronous orbit means it passes over any given point on Earth at approximately the same local solar time, ideal for consistent Earth observation lighting conditions. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is ~10–25 years. Orbital Radar tracks CP4 in real time using the latest two-line element set (TLE) data, providing live position, altitude, speed and orbital path updated continuously.

CP4 orbits at an average altitude of 672 km in a sun-synchronous orbit (SSO), a specialised subset of LEO where the orbital plane precesses to maintain a constant angle relative to the Sun. This provides consistent lighting conditions on every pass — essential for Earth observation, weather monitoring and environmental science. Within ±50 km of CP4’s average altitude, there are currently 574 active payloads and 1,214 tracked debris or rocket body fragments — notable neighbours include TERRA, AQUA, LANDSAT 9. With an inclination of 98.4°, CP4 passes over latitudes between 98.4°N and 98.4°S, providing near-global coverage including the polar regions. Polar and near-polar orbits are used for reconnaissance, weather monitoring and Earth-observation missions that need to image every part of the planet. United States operates approximately 12,360 active satellites in total, of which 276 share a similar altitude band with CP4.