![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)
[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 […]
SETI
Posted inBiosignatures & Paleobiology
Substrate-Agnostic 3x: Biosignatures, Technosignatures, Ecologies
[physics.gen-ph] Substrate-agnostic perspectives are currently attracting increased attention. For example, it has become customary to refer to agnostic biosignatures to reflect the range of alternative extraterrestrial biospheres and to account […]
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 […]
![Images in the JWST/MIRI F560W, F1000W and F1500W filters (central wavelength ≈ 5.6, 10 and 15 𝜇m) of candidates D (first row) and E (second row). White stars mark the Gaia positions of the M dwarfs, which in both cases are seen to be located ≈ 1 arcsec from the centres of background galaxies. -- [astro-ph.GA]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/07/Project-Hephaistos.png?resize=1200%2C720&ssl=1)
Posted inSETI & Technosignatures
Project Hephaistos — IV. James Webb Space Telescope Observations of Two Dyson Sphere Candidates
[astro-ph.GA] We report on JWST/MIRI imaging and spectroscopy of two M-dwarf stars previously singled out by project Hephaistos as potential Dyson-sphere candidates (their candidates D and E) due to the […]
![Candidate component r55 with period of P0 = 18.87 s in 1050–1140 MHz (a) and r952 with period of P0 = 16.58 s 1300–1450 MHz (b) in our search. The layout of the two panels are the same as Figure 1. -- [astro-ph.IM]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/07/Periodic-Radio.png?resize=1200%2C720&ssl=1)
Posted inSETI & Technosignatures
Periodic Radio Technosignature Search Toward 3I/ATLAS With FAST
[astro-ph.IM] 3I/ATLAS, the third confirmed interstellar object discovered in the Solar System, provides a unique opportunity for targeted technosignature searches.
Posted inSETI & Technosignatures
SETI’s Blind Spot: Technological Acceleration And Fleeting Technosignatures
[astro-ph.IM] The search for extraterrestrial intelligence (SETI) has traditionally framed the detection challenge with a focus on the parameter L in the Drake equation – the communicative lifetime of a […]