Science: Sunspot Upturn

All over the world last week astronomers expectantly watched the sun. Close to the solar equator a few small sunspots appeared, lasted a day or so, disappeared —sparse and sickly survivors of a decade-long sunspot cycle whose heyday was five years ago. The telescope men were looking for first signs of a new cycle—vigorous black splotches in the neighborhood of 30° north and south latitude, with magnetic polarities reversed in respect to the spots of the dying cycle. They had been looking for months, might have looked for months more (for sunspot changes cannot be forecast like eclipses) had not Dr. Seth Barnes Nicholson of Mt. Wilson Observatory reported two heralds of the sunspot upturn, slyly adding that he saw a first and fainter one a month ago. Sunspots seem to be whirlwinds—the mouths of spiral disturbances arising from below the surface. Hot gases emerging from the vortex expand and cool, thus make the spot look comparatively dark. Though no explanation of the cause of the disturbances has been confidently advanced, the shifting combination of gravitational pulls exerted by the planets is possibly involved. Visible spots range in size from a few hundred to 50,000 mi. across. They wax & wane in cycles which average 11.2 years, although the last two cycles covered hardly more than ten years each. As a cycle progresses the sunspot zones migrate from 30° north and south latitude to 16° in mid-cycle; the last survivors hug the equator. What interests laymen most about sunspots is their influence on earth and earthlings’ welfare. Scientists scout some notions on this subject as silly superstitions, debate others, accept a few as well substantiated. They agree that during high sunspot activity:

1) There are terrestrial magnetic disturbances which interfere with radio communication, occasionally with telephone & telegraph service.

2) The earthly aurora borealis is visible farther south. In July 1928 when sunspots were numerous Dr. Nicholson saw the Northern Lights in California.

3) More ultraviolet rays reach the earth.

4) The mean temperature of the air is about one degree C. cooler than during sunspot minima.

5) There is some effect on vegetation, evidenced by the record of sunspot cycles in tree-rings.

More dubious are the theories that sunspots affect the habits and numbers of animals, cause droughts, tidal waves, earthquakes, tornadoes. The withering drought of 1929 was close to a sunspot peak, but there were other drought causes—light snows, early thaws—the preceding winter. California’s Father Jerome Sixtus Ricard, S. J., “Padre of the Rains,” had astonishing success in predicting weather by sunspots, but Father Jerome is dead now and his secret seems to have died with him.

“Absurd!” says science to notions that sunspot activity brings influenza epidemics, wars, business prosperity. Prosperity undeniably reigned in 1928, the last sunspot maximum; the depression and the post-War slump were undeniably not far from sunspot minima. Carried further back, the correspondence collapses.