NASA recently released this picture Webb took of a Wolf-Rayet star back in June.
Wolf-Rayet stars are amongst the largest and brightest types of stars known. They form when massive stars, several times larger than our sun, begin to shed their outer layers. It’s a rare phase at the end of the stars life just before going supernova, and it’s said that these stars only last between a few hundred thousand to 1 million years. This may sound like a long time, but our own sun is estimated to live to 10 billion years old! Because of their short lifespan and low magnitude, we’ve only discovered around 1,000 so far in our entire galactic neighborhood. Thanks to infrared telescopes like Webb, however, we should see this number climb at a faster rate than ever before.
As the outermost layers are shed, the core and remaining gases heat up, producing stellar winds in excess of 2-5 million mph, which in turn speeds up the shedding process and causes the star to grow even brighter. Temperatures can easily reach 25,000K and there have been reports of temperatures as high as 200,000K! To put that into perspective, our sun is around 5700K(~10,000F).
Certain classes of these stars can be well over a million times brighter than the sun. However, most of their emissions are in the ultraviolet and infrared spectrums. So even though they’re extremely bright, they can actually be difficult to detect visually.
Luckily, we have telescopes like Webb that can see in this range. The raw image is taken in infrared and then converted to color so our minds can get an idea of what these stars and their surrounding gases look like.
You can find NASA’s article here: NASA’s Webb Telescope Captures Rarely Seen Prelude to Supernova | NASA
And more information on Wolf-Rayet stars can be found on the web (pun intended)