PROSPECTS OF A REAL SUNBURST

Otago Daily Times, Issue 18875, 30 May 1923, Page 5

PROSPECTS OF A REAL SUNBURST

If our sun should increase many hundred or a thousand times in light and heat in the brief space of a few hours or days, the coal shortage would become a problem of minor importance. And it seems there is a possibility that just that may happen some fine day, and bring to pass the predictions of a flaming end of the world. , One of the spectacular phenomena of the starry sky is the appearance now and then of,a “nova,” or temporary star. Twenty years ago such an outburst was thought a rare thing, but now novas are being discovered on photographic plates taken at the Harvard College Observatory and at the southern branch of the ’ observatory at Arequipa, Peru, at the rate of eight or 10 a year. If this represents' the average frequency of the outbursts of novas among the stars in the past as well as in the present, and if we conservatively estimate the age of the earth as 1,000,000,000 years, it is evident, says Isabel M. Lewis, of the United States Naval Observatory in Science Service’s Science News Bulletin (Washington); that since our planet came into existence something like eight or ten thousand million novas have appeared in the heavens. She goes on:

“This is considerably in excess of the estimated total number of luminous stare in the heavens. Thus it is reasonable to conclude that -all the stars in the heavens, including our own sun, have passed at least once and possibly severhl times through the ‘ temporary -1 stage. “Novas appear exclusively in the Milky Way or that belt of the heavens toward which the great majority of all the visible stars tend to crowd, and in which appear also vast tracks of nebulosity, luminous and iion-luminous.. Though there is still considerable doubt regarding the origin, of novas, it is generally considered that they are produced by the encounter of a star with nebulosity drifting through space, or with members of a meteoric swarm of considerable size. The examination of Harvard plates covering the same field of stars taken at intervals of days, months, or years shows that the sudden increase of a star many hundred or even thousand-fold in brightness during a few hours or days is preceded in some cases by peculiar fluctuations in the brightness of' the star for a number of years. This was true of the brilliant nova of 191, which for a few days outshone all the stare in the heavens with the exception of Sirius. “The novas that have been discovered in the systematic search for these objects at the Harvard College Observatory were in general too Taint even at the height of their outbursts to be visible to the naked eye. Under normal conditions preceding the outbursts they were usually either too faint to appear at all on the plates covering the region in which they later appeared or they were barely visible. “After the sudden outburst of a nova there is a more or less rapid return of the star to approximately its former brightness. Apparently it is chiefly the atmosphere of the #tar that is affected by the catastrophe. In practically every instance it has been noted that the star is wrapt for some time in nebulosity after its sudden outburst.

“There may be many stars in the heavens that' have experienced such a celestial catastrophe and recovered from it. Though a star may recover to a great extent from the effects of such an outburst, it is certain that a_ celestial catastrophe in which the intensity of the star’s light increases many thousandfold would bring about a complete destruction of life on its planetary worlds if such existed.”