Astronomers solve mystery of 'Green Monster' in famous supernova remnant (photo)
The mysterious wispy green light captured by the James Webb Space Telescope last year near the heart of Cassiopeia A turns out to be a result of a blast wave slamming into surrounding material.
![Astronomers solve mystery of 'Green Monster' in famous supernova remnant (photo)](https://cdn.mos.cms.futurecdn.net/DjsEfBFyGLyd45sn8S5bVX.jpg?#)