Footnote

b In 1995, scientists noticed the strange behavior of the most distant star (SN 1995K) ever observed as it exploded in its galaxy. Like supernovas in nearby galaxies, this star became very bright and then slowly faded but over a longer period than ever before detected. New Scientist magazine plotted this on a graph and explained: “The shape of the light curve . . . is stretched in time by exactly the amount expected if the galaxy was receding from us at nearly half the speed of light.” The conclusion? This is “the best evidence yet that the Universe really is expanding.”