Ever since two astronomers discovered a potentially bright comet called ISON a year ago, excitement has built over the possibility of this comet being incredibly bright. Maybe historic. Maybe the brightest comet anyone now alive has ever seen. Maybe the brightest comet ever to appear in Earth’s skies. Soon after the first predictions for the comet were revealed, numerous news reports suggested ISON may, late this year, be “as bright as the Full Moon.”
Well, in truth, the ephemeris, the calculations of the comet’s orbit and predictions of its behavior, were revised several times. And the predicted brightness of the comet worked its way downward. Not a huge amount, but a little. Enough to start making people nervous…..
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