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Comet Encke photographed by Fritz Helmut Hemmerich. Notice how the comet appears to have three tails. One tail is the dust tail. As the image was taken, the gas or ion tail was split by the turbulent solar wind.

This artist’s impression shows what the very distant young galaxy A2744_YD4 might look like. Observations using ALMA have shown that this galaxy, seen when the Universe was just 4% of its current age, is rich in dust. Such dust was produced by an earlier generation of stars and these observations provide insights into the birth and explosive deaths of the very first stars in the Universe.