Comet Holmes, which was discovered in November 1892 by Edwin Holmes, in London England, was no brighter than magnitude 17 in mid-October—that's about 25,000 times fainter than the faintest star that can normally be seen without any optical aid. In order to view an object this faint, one would need a moderately large telescope.
But the comet's brightness has suddenly rocketed all the way up to 3rd-magnitude, brightening nearly 400,000-times in less than 24-hours! On this astronomers scale, smaller numbers mean brighter objects. From urban locations, a 3rd-magnitude object might be hidden by light pollution, but under rural skies it would be clearly visible.
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