The Reminiscent of tree rings The focused repeating pattern of dust captured by the Webb Space Telescope’s MIRI instrument in infrared around the star Wolf-Rayet 140, 5,300 light-years away. The last recording shows at least 17 episodes (one side incomplete), and previous recordings of this system showed only two such episodes.
Wolf-Rayet 140 is a pair of stars young and old whose members have orbited each other for 8 years. Both stars were type O at birth, these stars are very massive and hot. During the orbits of the two stars, the gases emitted by one star collide with the gas emitted by the other, and as a result, a concentric repeating pattern is formed.
The Webb Space Telescope’s MIRI instrument sees longer wavelengths in the infrared range, making it possible to observe less hot objects through it. The same is true for the now immortalized rings. MIRI was also able to examine the spectrum of the rings, which confirmed that they were generated by the Wolf-Rayet star.
The Wolf-Rayet star begins life as an O-type star and has a mass at least 25 times that of the Sun, which also means that it will likely collapse into a black hole at the end of its stellar existence. Half of the pair under investigation now belongs to this type, and thanks to the increased heat, amazingly strong stellar winds sweep a huge amount of gas from the star, which then turns into dust. According to estimates, this star has already lost more than half of its mass during this cosmic diet.
However, hydrogen, the most common component of stars, cannot turn into dust on its own. However, since the Wolf-Rayet star emits a very large amount of material, in addition to hydrogen, other elements are also released from it, which are otherwise formed in the depths of the star, such as carbon. These elements cool as they move away from the star, and where the stellar winds of the two stars meet, like kneading the dough of hands, these gases compress.
The comparison figure shows the Sun in the upper left corner, the Wolf-Rayet star (left) and an O-type regular star (right) at the bottom. In the system examined, the mass of the O-type member is almost 30 times that of the Sun, and the Wolf-Rayet star. 10 times.
Source: NASA / JPL-Caltech
Other Wolf-Rayet systems also create dust, but none have the “ring of the year” shape of this duo. This strange appearance is due to the fact that the star of the Wolf-Rayet pair has a long orbit, because the Wolf-Rayet pairs that orbit in circular orbits constantly produce dust.
strange system is natural astronomy Its properties were presented and highlighted by a large international research group in a journal. The researchers came to the conclusion that the Wolf-Rayet 140 winds also swept away the remaining material from the ocean of stars, thanks to which the rings preserve their original structure very beautifully. In all likelihood, there may be more rings surrounding the system, but they have become so weak as they recede that the James Webb Space Telescope cannot detect them. The researchers also modeled the birth of the rings formed by the two stars’ collaboration, which can be seen in the video above.
Although Wolf-Rayet stars may seem quite exotic, they also play a role in the formation of stars and planets. Material from these systems swept away by these stars can collect in the systems environment, and a new star could be born from them. There is evidence that the Sun may have been born under the influence of the Wolf-Rayet star. With the help of the Webb Space Telescope’s MIRI Spectroscope, it is now possible to demonstrate that these stars produce carbon-rich dust. Moreover, this dust appears to be able to withstand the vagaries of space and thus contributes to the material of later born stars and planets.
There is also a contradiction regarding the Wolf-Rayet stars: according to estimates, there must be at least a few thousand such stars in our galaxy, but only 600 have been found. Although these stars are short-lived, they are important because of their dust production. Hopefully, with the help of the James Webb Space Telescope, we can learn more about it!
