NASA Telescopes Chase Down "Green Monster" in Star's Debris

  • Released Wednesday, January 31, 2024

Animations of images originally published at and

Astronomers have combined data from NASA’s Chandra X-ray Observatory and James Webb Space Telescope to study supernova remnant Cassiopeia A (Cas A). This work has helped explain an unusual structure called the “Green Monster”. Composite images from Chandra, Webb, Hubble, NuSTAR, and Spitzer reveal where elements such as silicon, iron, and titanium are located. Comparing where certain elements are with the location of the blast wave, researchers conclude that the Green Monster was created by a blast wave from the exploded star slamming into material surrounding it.

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Please give credit for this item to:
X-ray: NASA/CXC/SAO; Optical: NASA/ESA/STScI; IR: NASA/ESA/CSA/STScI/Milisavljevic et al., NASA/JPL/CalTech; Image Processing: NASA/CXC/SAO/J. Schmidt, K. Arcand, and J. Major

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This page was originally published on Wednesday, January 31, 2024.
This page was last updated on Monday, February 5, 2024 at 12:31 AM EST.