Analysis of information sources in references of the Wikipedia article "வட்டணைகளின் பட்டியல்" in Tamil language version.
Low Earth orbit (LEO) – The region of space below the altitude of 2000 km., pages 37–38 (6–1,6–2); figure 6-1.
Transatmospheric orbit (TAO): orbital flight with perigee less than 80 km but more than zero. Potentially used by aerobraking missions and transatmospheric vehicles, also in some temporary phases of orbital flight (e.g. STS pre OMS-2, some failures when no apogee restart)
Low Earth orbit (LEO) – The region of space below the altitude of 2000 km., pages 37–38 (6–1,6–2); figure 6-1.