It is based on the construction of calibration graphs Δ2θ(2θ) from the results of processing K α 1 and K α 2 components of external reference reflections successively brought to the equatorial circumference. A Si single crystal is used as the reference. Random errors are estimated. ...
Greg Matloff, Harold Gerrish, in Interstellar Travel, 2023 3.1.2 Interplanetary space: The Astronomical Unit The Earth is a nearly perfect sphere with a radius slightly less than 6400 km (Lodders and Fegley, 1998). The circumference of our planet is therefore about 40,000 km. Low Earth Or...