[astro-ph.SR] The infrared-flux excess of stars harbouring Dyson spheres represent one potential technosignature of extraterrestrial intelligence.
![Blackbody spectra derived from the 𝑇eff of the Dyson sphere candidates A to J throughout the wavelength range of 10 to 1000 microns together with the detection thresholds of telescopes Akari (Murakami et al. 2007), IRAS (Neugebauer et al. 1984), the ALMA 12∼m array6 and JWST/MIRI. In the case of JWST, both broadband imaging and spectroscopic limits (based on the LRS Slit or MRS7observations) are shown. In the case of JWST and ALMA, all limits refer to 5𝜎 confidence in 1 hour exposure time (where exposure times refer to observations per filter in the case of imaging; per band in the case of ALMA spectroscopy; per channel in the case of JWST/MIRI MRS spectroscopy and for the entire plotted wavelength range in the case of JWST/LRS spectroscopy). As can be seen, all candidates are detectable throughout some part of the wavelength coverage of JWST. The inset shows a zoom-in on the part of the spectral energy distribution that may be detectable with ALMA for four of the candidates (A, G, I and J). -- [astro-ph.SR]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/07/Project-Hephaistos-1.png?resize=1200%2C720&ssl=1)
[astro-ph.SR] The infrared-flux excess of stars harbouring Dyson spheres represent one potential technosignature of extraterrestrial intelligence.