HAO News

HAO News

Annie Maunder

Annie Maunder, A Pioneer of Solar Astronomy

If you have visited the High Altitude Observatory (HAO) at NCAR in Boulder, CO, you may recall seeing the Maunder’s original butterfly diagram. The chart resembles three butterflies traveling west. Drawn by Annie S.D. Maunder and E. Walter Maunder, it demonstrated for the first time the movement of sunspot emergence from the poles toward the equator over the sun's 11-year cycle.