The upload here doesn’t do justice to this incredible new shot of Cassiopeia A, one of the most spectacular supernoval remnants to be found in the sky. Imaged by the Webb Space Telescope’s near-infrared camera, the “high-resolution look unveils intricate details of the expanding shell of material slamming into the gas shed by the star before it exploded.”
The most noticeable colors in Webb’s newest image are clumps represented in bright orange and light pink that make up the inner shell of the supernova remnant. Webb’s razor-sharp view can detect the tiniest knots of gas, comprised of sulfur, oxygen, argon, and neon from the star itself. Embedded in this gas is a mixture of dust and molecules, which will eventually become components of new stars and planetary systems. Some filaments of debris are too tiny to be resolved by even Webb, meaning they are comparable to or less than 10 billion miles across (around 100 astronomical units). In comparison, the entirety of Cas A spans 10 light-years across, or 60 trillion miles.
“With NIRCam’s resolution, we can now see how the dying star absolutely shattered when it exploded, leaving filaments akin to tiny shards of glass behind,” said Danny Milisavljevic of Purdue University, who leads the research team. “It’s really unbelievable after all these years studying Cas A to now overcome those details, which are providing us with transformational insight into how this star exploded.”
This is the second shot of Cas A taken by Webb, following one produced with its mid-infrared instrument. Thumbnails below show the two side-by-side. In both, the invisible wavelengths of light captured by each device are shifted into the visible spectrum.
