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© D. Milisavljevic (CfA) & R. Fesen (Dartmouth)
Astronomers have produced a 3D map of the interior of Cassiopeia A, a supernova in our galaxy, using the astronomical equivalent of a CAT scan.

The Cassiopeia A, or Cas A, exploded around 340 years ago and its relatively close proximity to the Earth makes it one of the most well-studied supernovas in our galaxy. Many astronomers still observe the supernova with great interest.

A new study conducted by researchers at the Harvard-Smithsonian Center for Astrophysics and Dartmouth College unravels the bubbly interior of the supernova. The findings may shed more light on the way a supernova dies.

"Our three-dimensional map is a rare look at the insides of an exploded star," said Dan Milisavljevic of the Harvard-Smithsonian Center for Astrophysics.

Astronomers explain that when a star explodes, it spews out extremely radioactive and hot matter outward from the core of the star. It is complex to model such process even with some of the most powerful computers on Earth.

However, by cautiously studying the remnants of fairly young supernovae such as Cas A, astronomers can examine several key processes that drive such stellar explosions.

The scientists suggest that the latest research involved examining the debris to understand what blew and how it blew. They claim that this latest study is a step forward in understanding how stars explode.

To generate the 3D map, the research team observed Cas A in near-infrared wavelengths of light using the Mayall 4-meter telescope at Kitt Peak National Observatory, southwest of Tucson, Ariz. The team also examined very faint materials found in the interior of Cas A, which provided significant information.

The study found that large cavities in the interior of Cas A look as if they were connected to large debris in the outer part of Cas A. The scientists posit that two cavities were very well-defined and had a diameter of three and six light-years. The researchers say that the entire structure resembled that of a Swiss cheese.

The authors of the study explain that the bubbly cavities of the supernova were possibly produced by clouds of radioactive nickel that was generated through the star explosion. As the nickel decays and forms iron, the bubbly interior of Cas A becomes rich in iron, scientists believe.

Further examination of the supernova via next-gen telescopes is needed to understand the origination of the bubbly interior of Cas A, suggest the researchers.

The study was published in the journal Science.