NASA reveals what the green monster discovered by the James Webb Space Telescope is – Teach me about science

Discoveries in space do not cease or amaze us, some for their astonishing beauty and others for the peculiarity of their properties, such as the case of the giant structures of the Great Ring and Giant Sagittarius galaxies, which are celestial bodies, because, due to their nature that contradicts established theories about space, they should not exist. However, the universe shows us once again that there are many things that we do not know yet and that it has to offer to us.

Another example of this is the phenomenon that although it was discovered in April 2023 by the James Webb Space Telescope, scientists have not yet been able to find an explanation for its origin. However, a recent study has combined data from NASA's Chandra X-ray Observatory and the James Webb Telescope to better understand the origin of this phenomenon. Known as the “green monster,” this feature is part of the shock wave that borders the debris field of a stellar explosion, visualized as a ring of green light in the supernova remnant.

This “green monster” was discovered in the remnant of the Cassiopeia supernova (Cas A), which is located 11 thousand light-years from Earth, in the constellation Cassiopeia. This supernova remnant is a stellar explosion that caught the attention of astronomers, as the star that gave rise to Cas A had a short, though intense, life because it consumed its nuclear fuel at a somewhat accelerated rate. Therefore, at the moment of collapse, it created a powerful explosion that blocked out the light of its entire galaxy for a short moment.

When this happened, the light reached Earth more than 300 years ago, in 1671. Although this star was classified as a star by the British astronomer John Flamstead, there are no historical records confirming this event. The existence of an intense source of radio waves in Cassiopeia was not revealed until the twentieth century.

To get a better image of Cassiopeia A (Cas A) required joint collaboration between NASA's James Webb, Hubble, Spitzer, and Chandra telescopes, resulting in a never-before-seen detailed image. The Chandra X-ray Observatory captured the hot debris from that explosion, while the James Webb Observatory can detect hundreds of unchanged materials by these shock waves, which are known as “pristine.”

This study suggests that this object was created when a shock wave collided with material that the star had already shed, approximately 10,000 to 100,000 years before the explosion. Likewise, the study helped show that although the green monster appears in photos of Cas A, it is not part of it.

To be able to observe in more detail, the researchers eliminated the green monster with the help of a digital tool, and in this way it was possible to open the background and see everything that was hidden behind this wonderful phenomenon, near the center of Cass A. This was also an achievement, because it was the first time that the interiors of a supernova explosion had been observed in such detail and well preserved.

Scientific research will never stop moving forward, so this kind of discovery opens doors to new theoretical models, to deny and restructure those that have already been proposed or to confirm what has been thought about a topic. However, even if answers to some questions are found, more and more mysteries will always emerge that will shed light on the mysteries that the universe never stops presenting to us.