Table 4. Space debris population of ORDEM 3.0, MASTER-2009, and 3D Korean space debris model

Parameter	ORDEM 3.0	MASTER-2009	3D Korean space debris model
Population storage	Yearly	Quarterly	Quarterly
Analysis interval	Yearly	Any interval	Any interval
Analysis time period	2010–2035	1957–2060	2024–2060
Orbital regime	LEO-to-GEO	LEO-to-GEO	LEO (2024), MEO-GEO (2026)
Population data sources	In-situ: STS returned surfaceRadar: SSN (TLE)Telescope: MODESTGround tests: SOCIT4	In-situ: LDEF, EuReCa, HST returned solar panelsRadar: SSN (TLE), TIRA, EISCATTelescope: ESA-SDTGround tests: SOCIT4, AEDC SRM burn SOURCE	Radar: SSN (TLE)Telescope: OWL-Net (Korean optical space surveillance system)(Jo et al. 2015; Choi et al. 2018; Park et al. 2018)

ORDEM and MASTER-2009 data from Krisko et al. (2015).
ORDEM, orbital debris engineering model; MASTER, meteoroid and space debris terrestrial environment reference; LEO, low Earth orbit, GEO, geostationary Earth orbit; MEO, medium Earth orbit; STS, space transportation system, SSN, space surveillance network; TLE, two-line element; LDEF, long duration exposure facility; HST, hubble space telescope; MODEST, Michigan orbital debris survey telescope; SOCIT, space object catalog identification task; TIRA, tracking and imaging radar; EISCAT, European incoherent scatter scientific association; ESA, European Space Agency; SDT, space debris telescope; AEDC, arnold engineering development complex; SRM, solid rocket motor.