BLOCK DM-SL R/B

BLOCK DM-SL R/B is a spent rocket body associated with Sea Launch, launched on 2002-06-15 from Sea Launch (ocean platform) on the Galaxy III-C launch. With over 24 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Highly Elliptical Orbit (HEO) at altitudes between 365 km and 40,773 km with an inclination of 0.9°. It travels at approximately 13,848 km/h (3.85 km/s), completing one full orbit every 12 hours 14 minutes — that’s roughly 1.96 orbits per day. Its orbital eccentricity of 0.7500 gives it a noticeably elliptical path, with significant altitude variation between perigee and apogee. Spent rocket bodies like BLOCK DM-SL R/B are among the largest pieces of uncontrolled space debris and are priority targets for collision avoidance manoeuvres and future active debris removal efforts.

BLOCK DM-SL R/B follows a Highly Elliptical Orbit, sweeping between 365 km (perigee) and 40,773 km (apogee). It spends most of its 12 hours 14 minutes orbital period near apogee, effectively loitering over a region of interest before rapidly sweeping through perigee — a profile used for high-latitude communications (Molniya orbits), early-warning systems and magnetospheric science. Within ±50 km of BLOCK DM-SL R/B’s average altitude, there are currently 0 active payloads and 8 tracked debris or rocket body fragments. This is a relatively sparse altitude band, containing less than 1% of all active satellites. With an inclination of 0.9°, BLOCK DM-SL R/B passes over latitudes between 0.9°N and 0.9°S, concentrating coverage over equatorial and near-equatorial regions. Low-inclination orbits maximise revisit rates over specific tropical zones.