OPTIMIST CLUB.

Wairarapa Daily Times, 21 October 1930, Page 5

OPTIMIST CLUB.

TALK ON ASTRONOMY. At the Optimist Club luncheon today, Mr B. Iveson, who was the chief guest and speaker, gave an interesting address on some aspects of astronomy. “It is in Chaldea,” said Mr Iveson, 11 that we find the beginnings of astronomy. From this ancient Empire comes the zodiac; the week of seven days in honour of the seven then known “heavenly bodies,” the sun, moon and five planets; the division of the year into twelve months; the day into 24 hours; the hour into sixty minutes, and the minute into sixty seconds. Here, too, originated the system of weights and measures. Stars are vast globes of white hot metal, surrounded by an atmosphere of white hot or red hot gas. There are three thousand million stars, and of these only 6000 can be seen by the naked eye. Some of the stars are so far away that the light from them, travelling at the tremendous rate of 186,000 miles per second, takes thousands of years to reach the earth. The sun - is, approximately, one thousand times bigger than the earth, yet many of the stars are bigger than the sun. The nearest star to the earth, Proxima Centauri, is 22 billion miles from the earth. Alpha, one of the pointers of the Southern Cross, is 26 billion miles from us, and the light from this star takes years to reach us, travelling at the rate of 186,000 miles a second. These two are our- nearest starland neighbours. Compared with some of the stars, our sun is a midget. For instance, the sun has a diameter of one million miles; yet the star Canopus is sixty million miles across, is three hundred thousand times the volume of the sun, and 4000 times more brilliant. Light from it takes 29;6 years to reach the earth; that is to say, the light that enters our eye to-night from Canopus left that star when Royalist fought Roundhead in England, -and King Charles lost his head, and Cromwell set up liis Commonwealth. Then another star, Arcturus, is 47,500 times larger than the sun, and 1300 times more brilliant, while its light takes 136 years to reach the earth, the light of to-night having left at the time when Frence was in the throes of its terrible revolution. Alcyone, “the King of the Pleiades,” is one thousand times more brilliant than the sun. The most brilliant star cluster in the sky is that called the Pleiades, which is 1200 billion miles away from us and the light from which takes 200 years to reach us. There are one thousand stars in the -cluster, and fifty are bigger than our sun. The brightest star in the sky is called Sirius. It is 31 times brighter than the sun, and *its light requires 20 years to cover the vast space between it and the earth. Millions of stars are so far away that their speck of light imprinted on the photographic plate used for the purpose left them before Christ was born, while astronomers compute that the light from some stars requires 30,000 years to reach the earth. All this goes to show the vastness of what we know as our universe. ’ ’

After answering a number of questions, Mr Iveson was accorded a hearty vote oif thanks for his address.