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Andromeda`s starlight

Our neighbour in the cosmos, the Andromeda Galaxy is home to puzzling concentric rings of cold dust that may one day sparkle with stars, say astronomers. Using the Infrared Space Observatory, Martin Haas of the Max Planck Institute for Astronomy in Heidelberg, Germany, and his colleagues captured images of the galaWs cold gas at about257'C. These show two concentric rings about 30,000 and 40,000 light years front the centre, and a possible ring closer to the middle. The galaxy's visible starlight comes mainly from giant spiral arms. "It is so extraordinary that the galaxy has a completely different infrared and visible structure," says Haas. He thinks Andromeda's starlight will one day come mainly from the concentric rings, as the cold gas should eventually form stars (Scienc4 Vol 281, No 1689).