The distinctive blue bubble appearing to encircle WR 31a is a Wolf–Rayet nebula — an interstellar cloud of dust, hydrogen, helium and other gases. Created when speedy stellar winds interact with the outer layers of hydrogen ejected by Wolf–Rayet stars, these nebulae are frequently ring-shaped or spherical. via NASA ift.tt/1oEvGez
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Hubble's Blue Bubble was taken on February 22, 2016 at 01:00AM
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Hubble's Blue Bubble was taken on February 22, 2016 at 01:00AM
