Free Astronomy Magazine September-October 2024

10 SEPTEMBER-OCTOBER 2024 ASTRO PUBLISHING E xamples of typical confounding factors in the research of Suazo's team. The top row presents sources from the blends category, the middle row sources embedded in nebular regions, and the bottom row cases that fall into the irregular category. On these scales, irregular and nebular cases cannot be distinguished, but the nebular nature can be established by inspecting images on larger scales. [M. Suazo et al.] process, only seven stellar objects were found to be candidates for Dyson spheres, with infrared emis- sion levels not clearly attributable to astrophysical processes. The researchers write: “All sources are clear mid-infrared emitters with no clear contaminators or signatures that indicate an obvious mid-in- frared origin. The presence of warm debris disks surrounding our candi- dates remains a plausible explana- tion for the infrared excess of our sources.” They add: “After analyzing the optical/NIR/MIR photometry of ~5x10 6 sources, we found seven ap- parent M dwarfs exhibiting an in- frared excess of unclear nature that is compatible with our Dyson sphere models. There are natural explana- tions for the excess infrared coming from these seven, but none of them clearly explains such a phenomenon in the candidates, especially given that all are M dwarfs.” Effectively, the seven candidate ob- jects appear to be red dwarfs (or M dwarfs, if you prefer), and it is known that dust and debris disks around this type of star are very rare. Furthermore, they form and present themselves differently than the disks of more massive stars. All in all, these candidates do not seem to have the properties necessary to produce the quantity of infrared radiation de- tected based on natural origins alone. Only an EDD (Extreme Debris Disk) could explain the infrared ex- cess of the seven candidates, but this type of disk has never been observed around red dwarfs. Aside from the fact that (as high- lighted by Suazo and colleagues) fur- ther spectroscopic analyses will be needed to resolve the issue, the probabilistic percentage that one or more candidates are Dyson spheres will hardly be greater than zero. It is well known that red dwarfs, with their frequent and very intense flares, are absolutely hostile to life as we know it. Planets orbiting in the habitable zone of a red dwarf, there- fore very close to the star (given the small mass of the latter), are bom- barded for hundreds of millions or