SOMETHING WRONG WITH THE SUN. 121 



might permanently lose so much of his heat and lustre 

 that the inhabitants of earth would suffer. Tacchini's 

 observation reminds us, however, that processes are at 

 work upon the sun which admit of being checked or 

 increased, interrupted altogether or exaggerated so 

 violently, that the whole aspect of the sun, his condition 

 as the fire and lamp of the planetary system, may 

 be seriously affected. 



If we only remember that our sun is one of the stars, 

 not in any way distinguished, unless perhaps by relative 

 insignificance, from the greater number of the stars 

 which illuminate our skies at night 01 are revealed 

 by the telescope, we shall learn to recognise the possi- 

 bility that he may undergo marked changes. There 

 are stars which after shining with apparent steadiness 

 for thousands of years (possibly for millions of years 

 before astronomy was thought of), have become sud- 

 denly much reduced in brightness, or after a few 

 flickerings (as it were) have gone out altogether. 

 There are others which have shone with equal steadi- 

 ness, and have then suddenly blazed out for a while 

 with a lustre exceeding a hundredfold that which they 

 formerly possessed. It would be equally unpleasant 

 for ourselves whether the sun suddenly lost the best 

 part of his light, and presently went out altogether, or 

 whether he suddenly grew fiftyfold brighter and hotter 

 than he now is. Yet in the present position of sidereal 

 astronomy, it is quite impossible to assert confidently 

 that one event or the other might not take place at 

 any time. 



