Hubble’s blue bubble in Carina
At the centre of this beautiful NASA/ESA Hubble Space Telescope image is a Wolf–Rayet star known as WR 31a, located about 30,000 light-years away in the southern constellation of Carina. The distinctive blue bubble is a Wolf–Rayet nebula — an interstellar cloud of dust, hydrogen, helium and other gases expanding at a rate of around 137,000 miles per hour.