Contents

28 January 1977
Vol 195, Issue 4276

About The Cover

The setting sun with a portion of the 22-degree halo and a V-shaped arc which touches it at the top. The arc was assumed to be the upper tangent arc until careful comparison with computer simulations revealed it to be an example of the Parry Arc. See page 360. [R. G. Greenler, University of Wisconsin—Milwaukee]