START First steps Deutsch Register : World Geodetic System 1984

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Defining constants Derived geometrical parameters of size of the Earth ellipsoid Derived geometrical parameters of form of the Earth ellipsoid Derived physical parameters IERS conventions 2010 for some important geodetic constants Additional parameters of the Earth (no WGS84 or IERS) Radian In the library
The World Geodetic System 1984 (WGS84) is the most important modern geodetic coordinate frame.

START First steps Deutsch Defining constants

Radius of equator (semi major axis of meridian ellipse) a=N90° 6 378 137.0000 m
Earth flattening f 1:298.257 223 563
  = 0.003 352 810 664 748
Geocentric gravitational constant (incl. atmosphere) GM 3 986 004.418·108 m³/s²
Angular velocity of Earth´s rotation ω 7 292 115.0·10-11 rad/s

START First steps Deutsch Derived geometrical parameters of size of the Earth ellipsoid

Semi minor axis of meridian ellipse b 6 356 752.3142 m
Radius of meridian curvature at the equator M 6 335 439.327 m
Radius of polar curvature c=M90° 6 399 593.6258 m
Radius of Gaussian mean curvature at the Equator Ro6 356 752.314 m
Mean radius of semi-axes R1 6 371 008.7714 m
Radius of sphere of equal area R2 6 371 007.1809 m
Radius of sphere of equal volume R3 6 371 000.7900 m
Meridian quadrant mP 10 001 965.7293 m

START First steps Deutsch Derived geometrical parameters of form of the Earth ellipsoid

Second flattening 0.003 364 089 820 976
Third flattening n0.001 679 220 386 384
First eccentricity 6.694 379 990 14·10-3
Second eccentricity e´²6.739 496 742 28·10-3
Linear eccentricity E521 854.008 423 39 m

START First steps Deutsch Derived physical parameters

Gravity potential at the geoid Uo62 636 851.7146 m²/s²
Second degree zonal harmonic C20-0.484166774985·10-3
Dynamic form factor -C20·√5= J2 1.08263·10-3
Normal gravity at the equator on the level ellipsoid γe9.780 325 3359 m/s²
Normal gravity at the poles on the level ellipsoid γp9.832 184 9378 m/s²
Mean value of normal gravity γ9.797 643 222 2 m/s²
Normal vertical gravity gradient ∂γ/∂h-3.09·10-6 s-2
Hydrostatic flattening fh1:299.7 = 0.003337

START First steps Deutsch IERS conventions 2010 for some important geodetic constants

Newtonian constant of gravitation G(6.67428±0.00067)·10-11 m³/kg/s²
Geocentric gravitational constant (incl. atmosphere) GM(3 986 004 418±8)·105 m³/s²
Radius of equator (semi major axis of meridian ellipse) a(6 378 136.6±0.1) m
Inverse flattening (flattening factor) 1/f298.25642±0.00001
Dynamical form factor J2(10 826 359±1)·10-10
Angular velocity of Earth rotation ω 7 292 115·10-11 rad/s
Gravity potential at the geoid Wo(62 636 856.0±0.5) m²/s²

START First steps Deutsch Additional parameters of the Earth (no WGS84 or IERS)

Mean air pressure at sea level 1013.25 mbar
Mean vertical air pressure gradient at sea level at 15°C 0.12 mbar/m
Mean refractive index of air close to the Earth surface 1.000293
Mean coefficient of refractivity 0.13
Velocity of light in a vacuum 299 792 458 m/s
Orbital velocity at Earth surface 7.91 km/s
Escape velocity 11.2 km/s
Minimum orbital period of an Earth satellite (theoretical) 1 h 24 min 18 s
Mean sidereal day 23 h 56 min 4.091 s
Gravitative time dilation -1.09 · 10-16

START First steps Deutsch Radian

Grad ρgon = 200 gon/π 63.66198 gon
Degree ρ° = 180°/π 57.29578°
Arcminuteρ` = 10800`/π 3437.747`
Arcsecondρ`` = 648000``/π 206264.8``
Did you know? You may get all numbers either with decimal point or with decimal comma.

START First steps Deutsch In the library

Link Author(s)Title Year Type Pages
MByte
PDF: open accessPoutanen M, Rózsa SzThe Geodesist’s Handbook 20202020343
0.1
PDF: open accessPetit G, Luzum B (Eds.)IERS Conventions (2010)2010179
2.9
PDF: open accessSandwell DTReference Earth Model - WGS8420027
0.1
PDF: open accessNational Imagery and Mapping Agency (NIMA)World Geodetic System 19842000175
0.1
PDF: open accessMoritz HGeodetic Reference System 198019846
0.2