[Reading Science] A Massive Star Just Before a Supernova Explosion

US NASA Releases Images Captured by JWST

The "Eye of Humanity," the James Webb Space Telescope (JWST), has delivered another rare astronomical observation. It has captured detailed images of a massive star, about 30 times the size of the Sun, in the moments just before it undergoes a supernova explosion.

NASA revealed on the 14th (local time) images taken by JWST of WR 124, located in the constellation Sagittarius about 15,000 light-years from Earth. This star is one of the Wolf-Rayet stars, which are extremely hot (30,000 to 200,000 K) and tens of thousands of times brighter than the Sun. These massive stars pass through the Wolf-Rayet phase briefly as they die, making them difficult to observe. This type of star was first discovered in 1867 by French astronomers C. Wolf and G. Rayet.

Wolf-Rayet star WR 124 in Sagittarius, located 15,000 light-years from Earth, just before a supernova explosion. Photo by NASA

JWST captured this star just before it began full operations in June last year. A close look at the photos shows that WR 124 is shedding its outer layers just before the supernova explosion, producing gas and dust that create a distinctive halo. It is a massive star more than 30 times heavier than our Sun and has already expelled gas and dust amounting to more than ten times the mass of the Sun into space. Astronomers are particularly interested in the dust emitted by WR 124. NASA explained, "Dust gathers to form stars and planets and serves as a platform where molecules, including those that make up life on Earth, are created and clumped together." They added, "Despite this essential role, we still do not have a theory that can explain how much dust exists in the universe."

However, with JWST's specialty in infrared observations, which are well-suited for studying cosmic dust, its full mission has enabled in-depth analysis of space dust. NASA stated, "Before JWST, astronomers studying cosmic dust lacked sufficient information and data to research dust-producing celestial bodies like WR 124." They added, "Now, with JWST, we can study real-time data."