DELTA 1 DEB

DELTA 1 DEB is a tracked piece of space debris attributed to United States, launched on 1978-03-05 from Vandenberg SFB, California on the Landsat C launch. With over 48 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Low Earth Orbit (LEO) at altitudes between 763 km and 1,109 km with an inclination of 98.8°. It travels at approximately 26,589 km/h (7.39 km/s), completing one full orbit every 104 minutes — that’s roughly 13.88 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 ~100–500 years. As orbital debris, DELTA 1 DEB poses a potential collision risk to operational satellites in nearby orbits and is continuously monitored by the U.S. Space Surveillance Network and other tracking systems.

DELTA 1 DEB orbits at an average altitude of 936 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 DELTA 1 DEB’s average altitude, there are currently 315 active payloads and 1,129 tracked debris or rocket body fragments. With an inclination of 98.8°, DELTA 1 DEB passes over latitudes between 98.8°N and 98.8°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 12,358 active satellites in total, of which 89 share a similar altitude band with DELTA 1 DEB.