TIMED

TIMED is an active satellite operated by National Aeronautics and Space Administration (NASA)/Applied Physics Laboratory, Johns Hopkins (United States), launched on 2001-12-07 from Vandenberg SFB, California on the Jason launch. With over 25 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Low Earth Orbit (LEO) at altitudes between 580 km and 582 km with an inclination of 74.1°. It travels at approximately 27,259 km/h (7.57 km/s), completing one full orbit every 96 minutes — that’s roughly 14.95 orbits per day. Its near-circular orbit (eccentricity close to zero) means it maintains a very consistent altitude throughout each revolution. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is ~3–10 years. Orbital Radar tracks TIMED in real time using the latest two-line element set (TLE) data, providing live position, altitude, speed and orbital path updated continuously.

TIMED orbits at an average altitude of 581 km in the core of Low Earth Orbit, the most heavily utilised altitude band. The balance of moderate drag (limiting debris accumulation) and short signal path (enabling low-latency links and high-resolution imaging) makes this regime the default for most commercial and government missions. Within ±50 km of TIMED’s average altitude, there are currently 3,120 active payloads and 549 tracked debris or rocket body fragments — notable neighbours include ONEWEB-0050, STARLINK-3005, STARLINK-3090. This makes it one of the more crowded altitude bands, containing roughly 17.8% of all active satellites. With an inclination of 74.1°, TIMED passes over latitudes between 74.1°N and 74.1°S, covering most populated land masses in both hemispheres. This mid-inclination band balances global coverage with efficient launch energy requirements. United States operates approximately 12,413 active satellites in total, of which 2,558 share a similar altitude band with TIMED.