Astronomers reconstruct the chaotic birth of a 2500-year-old nebula

And it's all thanks to the death of an Earth-sized star as well as a few 'innocent bystanders.'
Sade Agard
The southern ring nebula (nircam and miri images side by side).
The southern ring nebula (nircam and miri images side by side).

NASA, ESA, CSA, and O. De Marco (Macquarie University). Image processing: J. DePasquale (STScI) 

The stunning Southern Ring Nebula, NGC 3132, was created when a star expelled most of its gas 2500 years ago. It was selected as one of the first five image packages from the James Webb Space Telescope (JWST).

According to a new study published in Nature, over 70 astronomers from 66 organizations in Europe, North, South, and Central America, and Asia have used JWST photos to piece together this star's chaotic death.

The research opens the door for future JWST nebula investigations. It sheds light on fundamental astrophysical phenomena, including binary star interactions and colliding winds, with implications for supernovae and gravitational wave systems.

The star's death engulfed 'innocent bystanders'

"It was nearly three times the size of our Sun but much younger, about 500 million years old. It created shrouds of gas that have expanded out from the ejection site and left a remnant dense white dwarf star with about half the mass of the Sun- but approximately the size of the Earth," said lead author Professor Orsola De Marco in a press release.

"We were surprised to find evidence of two or three companion stars that probably hastened its death as well as one more 'innocent bystander' star that got caught up in the interaction," she revealed.

The study also used images from the Hubble Space Telescope, the Gaia Space Telescope, the San Pedro de Mártir Telescope in Mexico, and the ESO's Very Large Telescope (VLT) in Chile for the reconstruction.

"When we first saw the images, we knew we had to do something. We must investigate! The community came together, and from this one image of a randomly chosen nebula, we were able to discern much more precise structures than ever before. The promise of the James Webb Space Telescope is incredible," said De Marco, president of the International Astronomical Union Commission on Planetary Nebulae.

"A messy death"

The team highlighted a scorching central star -- a white dwarf that has burned out its hydrogen-- shining at the nebula's center. "This star is now small and hot, but is surrounded by cool dust," said Joel Kastner, another team member from the Rochester Institute of Technology USA.

"We think all that gas and dust we see thrown all over the place must have come from that one star, but it was tossed in very specific directions by the companion stars," he explained.

Additionally, the team pinpointed several spiral formations extending from the nebula's center. They argue that these concentric arches relate to the presence of a companion star orbiting the primary star while it is shedding mass. And more than one of these companion stars exists!

The scientists also noticed pairs of bulges in a three-dimensional data reconstruction, which may happen when astronomical objects release matter in jets. These have an irregular form and radiate in many directions, which, the researchers claimed, could indicate triple-star interaction at the core.

"We first inferred the presence of a close companion because of the dusty disk around the central star, the further partner that created the arches, and the super far companion that you can see in the image," said De Marco.

Once we saw the jets, we knew there had to be another star or even two involved at the center. We believed there were one or two very close companions, an additional one at middle distance and one very far away. If this is the case, there are four or even five objects involved in this messy death."