Is the Sun Shrinking?

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Science  04 Apr 1980:
Vol. 208, Issue 4439, pp. 51-53
DOI: 10.1126/science.208.4439.51


Observations of 23 transits of Mercury in front of the sun between 1736 and 1973 show no indication of any significant change in the diameter of the sun. Regression analysis yields a decrease of the angular diameter, as viewed from the earth, of under 0.3 arc second per century (> 90 percent confidence limit). This limit is incompatible with the 2 arc seconds per century decrease obtained by Eddy for the equatorial diameter from direct observations made at the Greenwich Observatory and at the U.S. Naval Observatory.