Fig1_1 Distance of Sun

Fig1_1 Distance of Sun

Fig. 1.1 . Values of the solar parallax obtained from measurements of the parallaxes of Venus, Mars, and the asteroid Eros between 1850 and 1970. The solar parallax, designated by pĚ, is half the angular displacement of the Sun viewed from opposite sides of the Earth. The error bars denote the probable errors in the determination, and the points for 1941, 1950 and 1965 all have errors smaller than the plotted points. In the 1960s, the newly developed radar (radio detection and ranging) technology enabled the determination of the Sunís distance with an accuracy of about 1000 meters. The radar value of the solar parallax is 8.79405 seconds of arc.

Copyright 2010, Professor Kenneth R. Lang, Tufts University