SUNSPOTS.

Bruce Herald, Volume L, Issue 32, 30 April 1914, Page 4

SUNSPOTS.

The South Australian Government Astronomer, Mr G. I'. Dodwcll, states that the largo sun.spots referred to in ix recent cablegram indicated that tho sun's quiescent period i.s now probably over, and that a reawakening of sunspot activity is at hand. It is expected that tho outbursts of solar energy will become more frequent until they attaifn a maximum, about tho year ii)l7 As seen in the telescope at the Adelaide Observatory, thers is really a group of spots at tho present time ,tho largest showing a characteristic bright filament stretching across the centre. Tho group is situated in tho northern hemisphere of tho sun, and is about half-way across the disc. It is a feature of sunspots that they start in high solar latitudes, and gradually work, towards the Equator, where they die out. Every 11 years the number of and area affected by these outbursts reaches a maximum. Tho increase from tho minimum to the maximum is accomplished in about four years, but the decline to tho next minimum takcj longer, usually about seven years. The sun is, therefore, called a lato star. The turning point of the minimum period, which now .seems to have been passed, has been somewhat delayed, through some cause unknown. It is probably connected with the phenomenon of the double maximum in the years 190-5 and IDO7. A very remarkable connection has been .-shown to exist between sunspots and magnetic storms on the earth, and with the extent of" the oscillations which the magnetic needles go through day by day. The effect of these solar outbursts on the earth's weather has not yet been definitely traced, though it has been affirmed by many that it is probably marked by other 'atmospheric interactions. But that there is some effect in closed formation, especially of the type known ns cirrus, appears to be shown bv the investigation.l; carried oinn the Philippine Islands and other tropical places.