THE SOLAR SYSTEM

Otago Daily Times, Issue 23224, 23 June 1937, Page 7

THE SOLAR SYSTEM

TO THE EDITOR

Sir,—l have just been reading a short article in Saturday's Daily Times on the winter solstice, in which the writer tells us some interesting things and draws some nice comparisons between the immense size of the sun and his family of planets. That subject has always had a peculiar fascination for me, and I sometimes amuse myself thinking about them in an abstract sort of way. and figuring out what it all means. To those of your readers who have not seen the, planet Jupiter through a large telescope, I would suggest that they should lose no time in visiting the observatory and, for the small sum of sixpence, seeing him in all his glory and magnificence. Now. to be told that the sun is f 165.000. miles, in diameter and 1000 times' larger than <all the ' planets of the solar system put together is a staggering statement: but to arrest the attention of the average reader I would tell him that the sun would occupy all the space the earth occupies and right out to the moon's orbit' (all round) and nearly 200,000 miles furIher out (all round again). I think that presentation makes us " sit up and take notice." An airman with his machine flying day and night without stop at 100 miles an hour (if it were possible) would get across the earths diameter of 8000 miles in about 3J days. It would take him 360 days to get across the sun's diameter, if he were flying day and night at the same speed. The present writer was at school in 1874 when the planet 'Venus made a transit across the sun's face.' The planet Venus is over 7000 miles in diameter, and about halfway between the earth and the sun. Yet it appeared just a tiny spot on the surface of the sun, or like a bee in front of a goodsized circular hive! Jupiter is 1300 times larger than the earth, and has six moons round him, and takes quite 12 of our years to go once round the sun. But the statement that Neptune, the furthest out planet, about which we are really sure, takes no fewer than 164 of our years to complete one trip round the sun gives one some idea of the extent of the solar system. Again, there is no such thing in the universe as a state of rest. Everything is in motion, rapid motion too. Even the great sun, our source of light and heat, and " in whom we live and move and have our being," is shifting his position in space, a distance equal to his own diameter every 24 hours—that is. about 10 miles a second, arid he takes .his whole family of planets along with him. ' The solar, system seems to be like a large envelope shaped perhaps something like a watch, the sun and all the planets inside falling through space at nearly 1,000,000 a day. There is no cause for alarm. The nearest object to us in space is, I think, one of the stars of the Southern Cross. If that were the sun's objective in his journey through space, he would not reach it in the next 70,000 years. Job speaks familiarly in the Old Testament about Orion and the Pleiades. These constellations come nightly to ourselves much the same as Job saw them. He must have known things which few others knew, for he asks the question, "Who hanged the earth upon nothing?" Not till the coming of Copernicus is the idea mooted again. I hope some of your readers will {rive us some of their reflections on this absorbing subject. Thinking develops our brain just as physical exercise develops our limbs. There is nothing to fear in the realms of thought. Like the universe they are limitless and invite research.—l am, etc.. Astro. Balclutha, June 21.