The celestial image, which was taken by the European Southern Observatory’s Very Large Telescope in Chile, shows the planetary nebula of Abell 33, which has shed its outer layer and formed an extraordinarily perfect blue bubble of matter. The bubble is aligned with a star in the foreground of the picture, known as HD 83535, creating a diamond ring in space.
This image is remarkable in more ways than one. When old red giant stars are coming to the ends of their lives, they throw off their outer layers, creating colourful clouds of gas known as planetary nebulae. Usually these gas clouds are disrupted in some way, giving them irregular shapes. This planetary nebula, however, has remained perfectly round.
Abell 33’s original star is now on its way to becoming a white dwarf – a star that has collapsed in on itself, leaving a very dense and hot star which will slowly cool over billions of years.
It’s still an incredibly bright star at the moment, glowing hotter than our own Sun and illuminating the blue gas cloud that surrounds it. It can be seen in the picture above, just off the centre of the nebula, glowing white compared to the other golden stars.