A star that exploded in the supernova remnant Cassiopeia A (Cas A) has been captured in a breathtaking new image by NASA's James Webb Space Telescope. This was a part of the first-ever White House Advent Calendar, which was launched by the First Lady of the United States, Dr Jill Biden, to highlight the "Magic, Wonder, and Joy" of the holiday season, according to the American space agency.
Cas A is one of the most thoroughly researched supernova remnants across the entire universe. The tattered remains of the object have been gradually captured in a multiwavelength image by a combination of ground- and space-based observatories, such as the NASA/ESA Hubble Space Telescope.
Since infrared light is undetectable to human vision, scientists and image processors convert infrared light wavelengths into colours that can be seen. Colours were then assigned to several Near Infrared Camera filters in this most recent image of Cas A, and each of those suggests a different activity taking place inside the object.
"The most noticeable colours 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 debris filaments are equivalent to or less than 10 billion miles across (about 100 astronomical units), making them too small for even Webb to discern. By contrast, the whole of Cas A spans10 light-years, or 60 trillion miles, according to NASA.
Danny Milisavljevic of Purdue University, who leads the research team, added, "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. It's really unbelievable after all these years studying Cas A to now resolve those details, which are providing us with transformational insight into how this star exploded."
