LONG AFTER IT HAPPENED, astronomers discovered that a distant Milky Way star had dimmed for seven years. Between 2012 and 2018, the bloated red giant star, located some 26,000 light-years away in the constellation Sagitta, the Arrow, had become more than 60 times fainter (a drop of 4.5 magnitudes) than before. "Stars typically don't do this," says Anastasios Tzanidakis (University of Washington), who reported the find at the 241st meeting of the American Astronomical Society. He and colleagues think that the extremely long and deep dimming happened when a slowly orbiting companion, surrounded by a huge disk of absorbing dust, blocked the red giant's light.
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