IN THE DEPTHS OF SPACE.

Timaru Herald, Volume LXXXIII, Issue 13014, 29 June 1906, Page 3

IN THE DEPTHS OF SPACE.

The first thing to realise about the stars is the: immensity of the distances -which separate them from one another. If we attempt to express each distances as those of the stars in' ordinary units of measurement, we have' to deal in numbers which are quite beyond ony power of mental realisation. in order to get over this difficulty- astronomers have introduced a new unit for the measurement of steller distances. This is known as the light-year, or the distance which light, travelling at 186,000 miles per second, would traverse in a year. One very curious consequence follows from this way of measuring stellar distances. When we look at the starstrewn sky we are fathoming the depths, not merely of space, but of time. We see none of the stars as it exactly is at this moment, but as it was when the light which affects our retina set out upon its journey. And, as almost all visible stars are set at very various distances from the earth, we see them all at different periods. If we look at. the constellation of Orion, we see the bright star Betelgeux at the head of the constellation as it was 128 years ago, whilst Rigei at the foot is visible by light which must have started at least three centuries before it reaches us. Sirius, however, which " bickers into red and emerald" to the south-east of Orion, we see by light which onlv started eight or nine years ago. It is plausibly I suggested that some of the faintest stars visible in ou,r largest telescopes mav be as much as 00,000 light-yeaxs awav. * The new star which recently displayed itself in Perseus was shown by an ingenius tram of rearming to be 300 light-year distant, so that in 1902 we were able to watch the progress of a stellar conflagration which really occurred about the time of the Spanish Armada. An ingenious French astronomer has based on this fact the pleasant fantasy in which he imagines that a disembodied spirit, able to move with the speed of thought, and endowed with supernatural powers of vision, mav at will behold any incident which had ever taken p!ace on the earth-under ah open sky, by transporting itself through space to the point which the light waves emitted by that incident have reached ia tbcir erdles? journey. Shch a being, p.aced at the distance of Can opus, might cow be watching the massacre of St. Bartholomew; and by travelling thence in a straight line towards the earth it would be able to pass in panoramic view the whole subsequent, course of the world's history. Of course, there would be considerable gaps, due to clouds, to the rotation of the earth, and to the fact that a great part of the earth's history has been conducted indoors.' But the general idea is perfectly sound. The old tsuperst-itution* of the Recording Angel might be replaced by this modern discovery of the light waves which travel for ever out into • boundless space with their story of human actions and sufferings.