Meinl TF-M-AR Tuning Fork / Apsidis' Rotation (246,04 Hz / E3)

Apsidis' Rotation: If the sun is regarded as an observation point (heliocentric view), the earth describes an elliptical orbit around the sun, with the sun lying at a focal point of this ellipse. Thus the earth is sometimes close to the sun (perihelion) and sometimes further away from the sun (aphelion). Perihelion and aphelion are located at the ends of the major axis of the Earth's orbital ellipse. This connecting line is also called apsidal line. This line rotates once in about 110 000 years around the sun.