The Dominion. SATURDAY, SEPTEMBER 28, 1907, CHARTING THE UNIVERSE.

Dominion, Volume 1, Issue 3, 28 September 1907, Page 6

The Dominion. SATURDAY, SEPTEMBER 28, 1907, CHARTING THE UNIVERSE.

The presidential address. to the British Association, that assembly of the demi gods of Science, which, sat-in Leicester last month, was delivered by Sir David Gill, one of'the most eminent of'living astronomers. For many years Sir David has lived at Capetown, . and cast his plumb line to sound the almost uncharted depths, of this; the richest hemisphere of stars.' In his address, which Lord Kelvin declared was greater in charm and interest than any fairy tale ever told, he spoke enthusiastically of his Southern skies; and they are worth a boast, for-they contain nearly all the noblest stars, and all the first fourteen brilliants can be seen even from Wellington. The.South owns the finest constellation: Orion; the Cross and the Pointers; those kingly stars Sirius and Canopus; the brightest Pointer, Alpha Centauri; the • unique Magellanic clouds; Omega Centauri, the finest; s'tar cluster, in which 10,000 suns appear as a single dim light. Rich harvests await Southern observers. A well-equipped observatory in one of our best situations could not fail to bring honour to New Zealand, and fame to the Dominion astronomer. The centre of interest in astronomy is shifting from the planets to the stars, and from the solar system to tihe universe. The 36-inch and the 40-inch telescopes have reached the limits of the practicable. Atmosphere is now sought for instead of size of instrument. The keener eye of photography, and the analysing eye of Hie spectroscope, also threaten In displace direct vision.. These new instruments of research have kindled new ambitions in Hie astronomer, and offered hi in .new worlds to conquer. Hence Hie seventh sslvllitr ut ■ -:p'i i.-'. or the (iOflih Asteroid, or (he riMinls of Mar.v cease to lie. KiM object?, wiih

him. He sees a possibility of understanding the Universe, and he toils patiently at the approaches to the problem. First and foremost he 'desires acciiracy of measurement. Sir David Gill dreams of a terrestrial arc, carefully measured, from the Cape to the northern extremity of Russia—an arc 105 degrees long. This great work, once accomplished, would determine , the size and shape of the earth, and afford an accurate base for initial astronomical measurements. Still more important to the astronomer is the exact distance of the sun. That is the unit in all his celestial distances. His measures of the size of every planet and of the distance of planets and stars all depend on this unit. He is satisfied that he knows the solar distance within a thousandth part—but that margin of error is 93,000 miles, an amount that he grudges sorely. The problem is now being attacked in the rear. They no longer look at the sun himself, but away from him! at the Asteroids. There are hundreds of these little planets, probably thousands, between the orbits of Mars and Jnpiter. Their total mass, or weight, is ' only about one-hun-dredth- part of _ the earth's. Hence 7 they are minute and starlike in the telescope. • One of ■them is known to wander outside the orbit of Jupiter, and one of thorn, Eros, makes a loop inside that of Mars and comes occasionally within about fifteen millions of miles of the earth. It will be in this position in 1931, and. Sir David proposes a congress of astronomers next year to arrange for making the best of that' opposition. This means .that the position of all the small stars about the path that "Eros" will pursue should be carefully determined by_ as many observers as possible.' Then, in' 1931, they will be able to determine the parallax of- the minute wanderer.with the utmost accuracy. This would give the distance of "Eros" from the earth, and that being known all the distances in the solar 'system are solved; for Kepler's, .laws ■ supply the exact ratios. This method is not new. Sir David Gill applied it, to Mars thirty years ago, to Juno nearly thirty-three years ago, and to other asteroids ten years r ago. He hopes that in 193rthe present margin of error in the sun's distance will be reduced, at least, to one-tenth. Great mysteries surround the astronomer. He believes he has touched bottom in the star depths. His sensitive plate says there are no more, and that the wall of outer darkness lies beyond. .He estimates the stars at a hundred millions.' But what are their relations to one another and to the whole? Whither does this whirl of motions qarry them? Whence and wliither is Arcturus .speeding at 370" miles a second'? What energy pr,opels him, or control's him? Whither is'"the sun and; his train of worlds speeding at nineteen miles a second? He is heading for the bright star, Yega, seen low in the north, but is liis path straight? Do other stars accompany him?. Is he one of a group ? What is the meaning of the varied colours and spectra of stars? What are ''blaze stars" and what are variables? What is 'the genesis of a star? Has collision anything to do with it? Does a nebula condense into a sun? Is there a temperature 'at which ;atoms dissolve and all elements are reduced to one?' Do suns die by cooling? and is ours dying*, or is the Cosmos immortal ? *In order that some future generation may find a clue to the solution of, these, , and a thousand other thronging problems, astronomei'3 chart the sides,', analyse, photograph, measure and describe. They know not which fact will prove to be the key, so they lay up everything in store, believing that some greater Kepler or Newton, some Darwin of the stars, will one day be helped by accumulated facts to solve the problems that make the souls of the elect ache.