At one time the star seemed virtually to have disappeared,
as if all its substance had been expanded into the nebulous cloud, but
always there remained a stellar nucleus about which the misty spiral
spread wider and ever wider, like a wave expanding around a center of
disturbance. The nebula too showed a variability of brightness, and
four condensations which formed in it seemed to have a motion of
revolution about the star. As time went on the nebula continued to
expand at a rate which was computed to be not less than twenty
thousand miles per second! And now the star itself, showing
indications of having turned into a nebula, behaved in a most erratic
manner, giving rise to the suspicion that it was about to burst out
again. But this did not occur, and at length it sunk into a state of
lethargy from which it has to the present time not recovered. But the
nebulous spiral has disappeared, and the entire phenomena as it now
(1909) exists consists of a faint nebulous star of less than the ninth
magnitude.
The wonderful transformations just described had been forecast in
advance of the discovery of the nebulous spiral encircling the star by
the spectroscopic study of the latter. At first there was no
suggestion of a nebular constitution, but within a month or two
characteristic nebular lines began to appear, and in less than six
months the whole spectrum had been transformed to the nebular type.
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