The James Webb Space Telescope continues to make history, having just discovered what might be the most distant galaxy ever observed. Now it may have discovered its first supernova.
Using the NIRCam instrument, Webb researchers believe they have observed a supernova. They combined Webb data with Hubble data and discovered a bright object that may be a star that has just gone supernova.
When a huge star runs out of fuel and dies, it explodes as a supernova. As the star falls, most of its material is ejected in a massive explosion that emits a great deal of light. This light is so brilliant that it can be seen from a long distance away. One such bright flare was discovered by Webb in the galaxy SDSS.J141930.11+5251593. The telescope took two images of the galaxy five days apart, and the flash was less bright in the second, indicating that it is fading with time.
Even with Webb’s high sensitivity, this conclusion is somewhat startling. Because supernovae are transitory occurrences, meaning they don’t persist for very long, you have to be lucky to witness one.
Although the explosion occurred billions of years ago, we are just now witnessing it because light takes time to travel from the distant galaxy to us. Webb was not meant to detect supernovae, but researchers are making the most of the data so far and discovering unexpected uses for it.
The benefit of seeing such a target with Webb is that it will be able to observe the area around the supernova to examine its impacts and the aftermath of such a big explosion.
Understanding supernovae is crucial not just for understanding star life cycles, but also for gauging the universe’s expansion. Because they have regular levels of brightness and can be viewed from considerable distances, Type 1a supernovae are employed as « mile markers » for measuring distances.
