ELECTRICAL DISTURBANCES APPARENTLYOF ... - Soft.belastro.net

Jansky: Electrical Disturbances oExtraterrestrial Origin1393direction of arrival were plotted against time of day, a curve like thatshown in Fig. 5 would be obtained. The curve is dotted for that portionof the time during which the earth would be between the source of thewaves and the receiver. As will be seen from the figure, the horizontalcomponent of the direction of arrival changes 360 degrees in about24 hours, or in exactly 23 hours and 56.06 minutes since that is thetime required for the earth to make one complete revolution with re-APPARENT DIRECTION OFARRIVAL OF WAVES IN5PACEFig. 6-The effect of the earth's orbital motion on the direction of arrival asmeasured at the receiving location.spect to the stars. It is this difference between the length of the siderealday and the mean solar day (3.54 minutes of solar time) that accountsfor the uniformly progressive shift of the curves of Fig. 2 to the left.Fig. 6 will illustrate just how this shift takes place. This figureshows the earth in its orbit around the sun as seen from above. If, ashas been assumed, the direction of arrival of the waves has a rightascension of 18 hours, they can be represented by some such group ofarrows as shown at the left in the figure. When the earth is in the positionshown for June 21 then, regardless of the declination of the direc-