A Solar Outburst (?)

Abstract

REFERRING to the note on solar activity in your issue of July 20, I shall be glad to know whether any correspondent Observed a luminous outburst in the tail end of the great spot on the evening of July 16. I had been observing in the afternoon with an 8½-inch reflector, but remarked nothing of the sort. At 5.30, however (the sun having got beyond range of my reflector), I was observing him with a small refractor, power 12, and sun-cap, when I at once noted the luminous appearance in question. It was roundish and about the size of the small spot near following limb, and it was brighter than the bright bridge in the large group. I watched this bright spot until 7.30; next morning it had practically disappeared. Father Cortie courteously informs me that the Stonyhurst magnets were perfectly quiet on July 16, but that next morning, at 8.15, there was a “very small but sudden and sharp movement on both the declination and horizontal force curves.” By that time the locality where the luminous appearance occurred would not be far from central meridian. I also noticed a rosy hue pass over the bright bridge of great spot, but this may have been a mistake. I am, however, certain of the luminosity.