A Ring to Rule Them All
Since its discovery in 1779, the Ring Nebula has drawn in stargazers – when we stare at it, the Ring stares back. Now, Hubble’s next-generation Wide Field Camera 3 has trained its razor-sharp vision on this famous object, helping astronomers to understand the nebula’s structure like never before.
At the core of the Ring Nebula is a pinprick of bright, white light. That’s a white dwarf, the leftover core of a star a little bigger than our sun that burnt out a few thousand years ago. As stars lose their reserves of hydrogen, their outer atmospheres puff out and escape into space. These still-expanding clouds of gas, now about a light-year across in the Ring’s case, form so-called planetary nebulae. As they are irradiated by the white-hot white dwarf, the Ring’s clouds glow like a neon sign.
From these new observations, astronomers have learned that the nebula’s blue center, which protrudes through the doughnut of orange gas, is actually shaped like a football. The darker “spokes” on the inside of the reddish ring are towers of gas slightly denser than their surroundings. These formations are better able to resist being blown away by ultraviolet light from the white dwarf.
In the image, the deep blue color in the nebula’s center is emitted from atoms of helium. The inner ring’s sea-green glow is produced by hydrogen and oxygen, while the red of the outer ring traces nitrogen. The darker orange comes from sulfur.
To celebrate this new image, the Hubble Heritage team is encouraging science fans to take a picture of themselves holding up an image of the Ring – a printout, or even a display on a smartphone – wherever they are in the world. Check out our “Ring Around the World” project for more information.
Credit: NASA, ESA, and the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration