![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)
[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 […]
SETI & Technosignatures
![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 […]
Posted inSETI & Technosignatures
Decolonizing Technosignatures: Reimagining Technosignatures Through An Indigenist Lens
[astro-ph.IM] There exist numerous proposals for potential technosignatures that we can search for, but they all tend to be deviations from possible naturally occurring signals. That is, technosignatures tend to […]
Posted inSETI & Technosignatures
Multistage Rocket Optimization, Geophysics, and the Spacefaring Envelope of Habitable Super-Earths
[astro-ph.EP] Habitability is typically defined by whether a planet can support life, rather than whether it can support a technological civilization capable of escaping its gravity well.
![Geometry of the LTT 3780 planetary system at the time of our radio technosignature observations. The left panel shows the sky-plane (X–Y) view as seen from Earth, while the right panel shows the top-down (X–Z) view of the system. The orbits of planets b (blue) and c (green) are shown relative to the host star (yellow). Our observations from the ATA, mentioned in Table 1 on 5th November 2025, were timed to coincide with a planet–planet occultation (PPO), when planet b passes behind planet c along the line of sight, providing a unique configuration to search for radio technosignatures during mutual planetary alignment.-- [astro-ph.IM]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/07/A-Search-For.png?resize=1200%2C719&ssl=1)
Posted inSETI & Technosignatures
A Search For Narrowband Technosignatures From LTT 3780 With The Allen Telescope Array And The Karl G. Jansky Very Large Array
[astro-ph.IM] The LTT3780 system hosts two known exoplanets-LTT3780b, a rocky super-Earth, and LTT3780c, a temperate sub-Neptune-orbiting a nearby M dwarf on opposite sides of the radius valley. LTT3780c has been […]
Posted inBiosignatures & Paleobiology, Imaging & Spectroscopy, Intelligence & Language, Interstellar, Nanotechnology & SynBio, SETI & Technosignatures
Micron-Scale Technosignatures: How a Cubic Metre of Lunar Regolith May Begin to Constrain the Number of Past Technological Civilisations in the Galaxy
[astro-ph.EP] Building on Arkhipov’s proposal that technogenic artefacts may survive natural interstellar transport and accumulate on airless Solar System bodies, we examine the prospects for identifying micron-scale engineered particulate material […]
![Modes of interstellar expansion across two dimensions. The horizontal axis (expansion agent) runs from biological (crewed colonization, settlers, generation ships) to machine (autonomous probes, robotic seed systems). The vertical axis (visibility) runs from quiet (low-mass, low duty cycle, weak technosignatures) to loud (high-power, high waste heat, galaxy-scale signatures). The four quadrants summarize alternative expansion modes considered in the literature; the quiet expansion filter proposed in this paper occupies the lower-right quadrant (highlighted). -- [astro-ph.IM]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/07/Autonomous-AI-Cosmoindustry.png?resize=1200%2C717&ssl=1)
Posted inSETI & Technosignatures
Autonomous AI-Cosmoindustry and the Quiet Expansion Filter: A Threshold-Based Resolution of the Fermi Paradox
[astro-ph.IM] The Fermi paradox is sharpened, not weakened, by plausible extrapolations of artificial intelligence, autonomous robotics, in-situ resource utilization, orbital manufacturing, space-based computing, and uncrewed interstellar probes.
Posted inPeople Of Astrobiology
Carl Sagan Month: Call For Participation
[EAI] This year marks the 30th anniversary of the death of the renowned astronomer, science communicator and writer Carl Sagan. It is a global opportunity to bring science closer to […]