![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.
SETI & Technosignatures
Posted inSETI & Technosignatures
Breakthrough Listen’s Automated Commensal Technosignature Survey With MeerKAT
[astro-ph.IM] The search for extraterrestrial intelligence (SETI) is an ongoing effort to detect technosignatures, evidence of technologically capable life beyond Earth. Conducting a comprehensive SETI programme requires a large amount […]
Posted inSETI & Technosignatures
Could Alien Signals Be Hiding On A Different Radio Channel?
[RAS] Astronomers searching for signs of extraterrestrial intelligence may have been missing alien signals in part of the radio spectrum that has not recently been explored.
![Simulated light curve for a periodic laser beacon at fpulse = 413 Hz at d = 15 pc observed with a Dtel = 1 m telescope at a cadence of 10 µs. The upper panels show a short segment of the noiseless pulse signal (left) and the corresponding signal including the estimated noise contributions (right). The bottom panel shows the integrated folded pulse profile after combining 108 pulses, resulting in an expected SNR of approximately 5.99. -- [astro-ph.IM]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/07/The-Interstellar-Laser.png?resize=1200%2C716&ssl=1)
Posted inSETI & Technosignatures
The Interstellar Laser Beacons Hypothesis and the Cosmic Lighthouses Project
[astro-ph.IM] In this paper, we argue that in a realistic, resource-limited scenario senders whose intent is to maximize successful communication at the lowest cost will utilize very long-lived, pulsed beacons.
![Conservative CW mitigation demonstrated on a fully synthetic wideband radio dataset with realistic detector features. (a) Frequency spectrum before and after mitigation. Red shaded regions indicate the three cataloged anthropogenic CW tones at 137, 405, and 450 MHz (representing satellite downlinks, weather balloon telemetry, and South Pole station communications, respectively). These tones are removed via least-squares time-domain sine subtraction as described in the text. The orange dotted line marks an uncataloged narrowband feature at 285 MHz that is successfully preserved. (b) Time domain trace of the same waveform shown in panel (a), zoomed in to show the effect of mitigation around an injected nanosecond-scale broadband transient (dashed black line). The raw simulated trace before mitigation (light red line) is heavily obscured by CW interference. After subtraction of the cataloged tones, the mitigated trace (solid green line) shows significantly reduced coherent CW contamination, successfully recovering the underlying broadband impulsive signal and preserving both its original shape and temporal structure. -- [astro-ph.IM]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/07/Methodological-Synergies.png?resize=1200%2C720&ssl=1)
Posted inSETI & Technosignatures
Methodological Synergies Between Technosignature And UHE Neutrino Searches
[astro-ph.IM] Radio technosignature searches and radio-based ultra-high energy (UHE) neutrino experiments address different scientific questions, but share a closely related data analysis problem: identifying rare signals of unknown morphology within […]
Posted inSETI & Technosignatures
A Dual-Burst Geometrical Prescription For Concurrent Signaling
[astro-ph.IM] We propose a dual-burst implementation of concurrent signaling for technosignature searches.
![Robustness gallery (left to right). Yellow boxes denote detections morphologically classified as linear, while red boxes indicate signals with curvature. (a) Target drifting narrowband track + broadband impulsive transient, with the corresponding MSWNet cleaned map and predicted box. (b) Target + curved interfering track, with the cleaned map and predicted box. (c) Target + quasi-sinusoidally modulated interference, with the cleaned map and predicted box. (d) Target spanning patch boundaries (tiling), with the stitching result across patches. The brightened area is overlapping region and the green box is the equivalent detection obtained after cross-patch stitching. -- [astro-ph.IM]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/07/A-Wavelet-1.png?resize=1200%2C712&ssl=1)
Posted inSETI & Technosignatures
A Wavelet-Integrated Search Pipeline For Narrowband Technosignatures in FAST Observations of 33 Exoplanet Systems
[astro-ph.IM] Building on prior FAST targeted and blind SETI campaigns toward 33 exoplanet systems, we introduce a wavelet-integrated search pipeline for narrowband technosignature candidates in radio dynamic spectra.
![Temporal dynamics of simulated civilizations across ten scenarios. (A) Mean trajectories of global technology T(t) with ±1 standard deviation shaded. (B) Mean resource levels R(t) with ±1 standard deviation shaded. -- [physics.soc-ph]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/07/Projections-of-Earth.png?resize=1200%2C720&ssl=1)
Posted inSETI & Technosignatures
Projections of Earth’s Technosphere: Civilization Collapse-Recovery Dynamics and Detectability
[physics.soc-ph] How long a technological civilization remains active, and what determines whether it collapses or persists, is a central question for both projecting humanity’s future and assessing the prevalence of […]
![Multiwavelength images of the two > 4𝜎 SJH candidates. Top: KIC 6606183. Bottom: KIC 9834255. Columns: WISE W1–W4 and Aladin DSS colour composite. Nearby sources are visible but their physical association requires high-resolution imaging. -- [astro-ph.SR]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/07/Stellar-J.png?resize=1200%2C720&ssl=1)
Posted inSETI & Technosignatures
Stellar J-Harvesting: A Novel Angular Momentum Technosignature And First Search In The Kepler Field
[astro-ph.SR] We introduce Stellar J-Harvesting (SJH), a technosignature in which an engineered system extracts rotational angular momentum from a star.
![The Rapid ASKAP Continuum Survey (RACS) radio images of radio sources associated with candidates A (J1245-2652, top row) and B (J0356-4031, bottom row) are shown at three frequencies: 887.5 MHz (left), 1367.5 MHz (centre), and 1655.5 MHz (right), with each panel covering a field of view of 65" × 65" . White ellipses show the PyBDSF source fits from the RACS catalogues, with thick solid lines indicating the fits at the frequency of the image, while thin dashed lines show fits from the other radio frequencies for comparison. Large blue crosses (×) mark radio source positions for the corresponding frequency, and small blue plus signs (+) indicate positions at other frequencies. The red stars represent the Gaia positions propagated to the corresponding RACS observation epochs using the measured proper motions. -- [astro-ph.SR]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/07/Archival-Diagnostics.png?resize=1200%2C720&ssl=1)
Posted inSETI & Technosignatures
Archival Diagnostics for Potential Background Contaminants Of Project Hephaistos Dyson Sphere Candidates
[astro-ph.SR] We report on the diagnostic inspection of nine Project Hephaistos Dyson Sphere candidate M-dwarfs based on archival data. By comparing the Gaia positions, propagated to the AllWISE epoch, with […]