The spectacular end of a dying star

NASA’s James Webb Space Telescope has revealed details of the planetary nebula called Nebula NGC 3132 that were previously impossible to see.

Planetary nebulae are the layers of gas and dust that some stars expel as they die.

The nebula NGC 3132 is also informally known as the Southern Ring Nebula. It is about 2,500 light-years away from Earth.

The new observation shows the South Ring nebula in an almost frontal view, but if we could rotate it to see it from the side, its three-dimensional shape would be seen more clearly as two bowls joined at their base, moving away from each other with a large hole. in the middle.

Two stars, which are linked in a tight orbit, shape the local landscape. Webb’s infrared images present new details of this complex system. Stars, and their layers of light, are prominent in the near-infrared camera (NIRCam) image at left, while the mid-infrared instrument (MIRI) image ) on the right shows for the first time that the second star is surrounded by dust. The brightest star is at an earlier stage in its stellar evolution and is likely to eject its own planetary nebula in the future.

The two images described. The one captured by the NIRCam is the one on the left, while the one captured by the MIRI is the one on the right. (Photos: NASA, ESA, CSA and STScI)

Meanwhile, the brightest star influences the appearance of the nebula. As the two stars continue to orbit each other, they “churn” the gas and dust, producing asymmetric patterns.

Each layer represents an episode in which the dimmest star lost some of its mass. The thicker layers of gas towards the outer areas of the image were expelled earlier. The closest to the star are the most recent. Tracking these emissions allows researchers to look at the history of this system.

NIRCam observations also reveal extremely fine beams of light around the planetary nebula. Light from the central stars pours out where there are holes in the gas and dust, much like sunlight escaping through gaps in a cloud.

Since planetary nebulae exist for tens or thousands of years, observing the nebula is like watching a movie in extremely slow motion. Each shell ejected by the star gives researchers the ability to accurately measure the gas and dust that are present within it.

As the star sheds layers of material, molecules and dust form within these layers, changing the landscape even as the star continues to shed material. This dust will enrich the areas around it, expanding into what is known as the interstellar medium. And since it has a very long life, the dust can end up traveling through space for billions of years and become a new star or a new planet.

In a few thousand years, these delicate layers of gas and dust will dissipate into the space around them. (Source: NASA)