Planetary-mass binary systems raise questions about the formation of intermediate-mass objects Last year, astronomers studying the Orion Nebula with the James Webb Space Telescope (JWST) discovered an interesting, free-floating planet-mass object in the region. This discovery called into question established ideas about the formation of planets and stars. A new study adds new depth to the mystery surrounding these objects, called JuMBOs (Jupiter-mass binary objects). JuMBO is not a star or a planet. They were originally discovered by Mark McCaulin, a senior scientific advisor at the European Space Agency (ESA), and his colleagues. These objects were discovered in the Orion Nebula, a birthplace of new stars about 1,350 light-years from Earth. article news news February 24, 2024 His JuMBO object in the Orion Nebula: a discovery that pushes the limits of conventional understanding of stars and planets Planetary-mass binary systems raise questions about the formation of intermediate-mass objects Last year, astronomers studying the Orion Nebula with the James Webb Space Telescope (JWST) discovered an intriguing, free-floating planet-mass object in the region. This discovery called into question established ideas about the formation of planets and stars. A new study adds new depth to the mystery surrounding these objects, called JuMBOs (Jupiter-mass binary objects). JuMBO is not a star or a planet. They were originally discovered by Mark McCaulin, a senior scientific advisor at the European Space Agency (ESA), and his colleagues. These objects were discovered in the Orion Nebula, a birthplace of new stars about 1,350 light-years from Earth. His JuMBO object in the Orion Nebula: a discovery that pushes the limits of conventional understanding of stars and planets Illustration of the Jupiter-mass binary object (JuMBO) in the Orion Nebula. Source: Gemini Observatory / John Romberg To further study JuMBO, researchers used data collected by his Very Large Array of 27 radio telescopes at the U.S. National Radio Astronomy Observatory. Of all his 40 objects discovered by JuMBO, only one pair of his objects had radio signals detected. Particularly noteworthy is the “JuMBO 24” pair. The researchers found that both objects in the pair have masses 11 times greater than the mass of Jupiter. This makes these objects the most massive objects of their kind recorded by JWST. The mass of his remaining JuMBO exceeds the mass of the heaviest planet in the solar system by a factor of 3 to 8. His observed JuMBO radio signal had significantly higher intensity compared to radio signals characteristic of brown dwarfs. A brown dwarf is an object that had the potential to become a star, but failed to gain enough mass to fuse hydrogen into helium at its core like our Sun. Brown dwarfs typically have masses between 13 and 75 times that of Jupiter. JuMBOs are relatively small, hot gaseous bodies that exist in pairs. This makes them unique, as it has traditionally been assumed that only massive stars, rather than less powerful bodies, are most likely to exist in binary systems. About 75% of massive stars are in binary systems, and this proportion drops to 50% for Sun-sized stars and 25% for the smallest stars. Therefore, the probability of finding a brown dwarf in a binary star system is close to zero. Because JuMBO has less mass than a brown dwarf, it would not have existed in a binary star system if it had formed as a star. However, if JuMBO forms as a star, its large number in Orion suggests that for some reason the frequency of binary objects increases significantly at masses lower than that of brown dwarfs. . This cannot yet be taken into account in star formation models. If planetary-mass objects cannot be explained by existing star formation models, they may form as planets. However, it is difficult to explain whether the JuMBO pair formed as a planet from leftover material in the disk of its parent star. Some planets are known to be ejected from their parent star system due to gravitational effects, such as collisions with other star systems. This makes it a “rogue planet” object without a parent star, similar to his JuMBO in the Orion Nebula. However, the process of creating these “rogue planets” requires destroying pairs of planets that are bound together by gravity. Researchers still can’t explain why JuMBOs paired up. Attempts at explanation are complex.

source: https://iopscience.iop.org/article/10.3847/2041-8213/ad18ac