SETI Archives

Artist’s impression of the approach of a swarm towards Proxima b; at this point, a few seconds before closest approach, the swarm could be examining the planet’s nightside for techno- or bioluminescence. (This image is based on the artistic work of Dr. Mark A. Garlick.) -- astro-ph.IM

Alpha Centauri, Biosignatures & Paleobiology, Cubesats and smallsats, Exoplanets, -moons, -comets, Gaia Mission, Habitable Zones, Interstellar, Missions & Hardware, Proxima Centauri, Status Report

Science From The In Situ Exploration Of Tthe Proxima Centauri System

by Keith CowingApril 23, 2026April 23, 2026

In the future interstellar exploration at near-relativistic speeds will be possible using beamed energy laser propulsion.

Sperm whale at water's surface. Credit: NOAA Fisheries

Intelligence & Language, SETI & Technosignatures, Status Report

CETI / SETI: The Phonology Of Sperm Whale Coda Vowels

by Keith CowingApril 15, 2026April 15, 2026

Sperm whales (Physeter macrocephalus) communicate using series of clicks known as codas. In previous research, sperm whale codas have been shown to resemble human vowels acoustically.

The mass versus orbital distance of currently discovered and characterized exoplanets. Solar system planets are indicated as well. The hexagonal icons, indicating spectroscopic characterization studied done using JWST, are adopted from Espinoza & Perrin (2025). Direct imaging, currently limited to far out and large planets, will have to advance in sensitivity and contrast ratio to reach Earth-like planets. -- astro-ph.EP

Astrochemistry, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Status Report

Spectral Signatures From The Habitable Zone

by Keith CowingApril 13, 2026April 13, 2026

This work describes the context and approach for the detection of spectroscopic signatures from planets in the habitable zone of nearby stars.

Schematic overview of the data-processing workflow in this work. After splitting the 2C data into three antenna spectra, we first conduct a general comb diagnostics for each antenna, then perform per-antenna PCA decomposition, basis alignment, and periodogram/FT/ACF analysis. The component-level results are finally combined to distinguish non-shared periodic signals from shared or comb-like RFI. -- astro-ph.IM

Artemis & Lunar Exploration, Astronomy & Telescopes, Biosignatures & Paleobiology, Missions & Hardware, Moon, SETI & Technosignatures, Status Report

First Lunar Farside SETI Observations for Periodic Signals With The Low-frequency Radio Spectrometer Of Chang’E-4 Mission

by Keith CowingApril 12, 2026April 12, 2026

Chang’E-4 (CE4), the first mission to soft-land on the lunar farside, provides a unique opportunity for astronomical observations from an environment shielded from terrestrial radio interference, and thus serves as […]

Transmitted power vs wavelength to various star systems of potential interest. The red dashed line shows the current wavelength limit of reflective optics. -- Nature

Astronomy & Telescopes, Biosignatures & Paleobiology, Interstellar, SETI & Technosignatures, Status Report

X-ray And γ-ray Beam Interstellar Communication And Implications For SETI

by Keith CowingApril 11, 2026April 11, 2026

The possibility of detecting artificial signals transmitted by alien civilizations via collimated X-ray or gamma-ray beams is investigated.

The final accumulated nighttime light change area: A night-time view of Earth, capturing human activity across the eastern hemisphere of the planet through the emissions of artificial light. Derived from satellite images taken daily over the past decade, the image maps the dynamics of the human night-time activity, with golden areas experiencing brightening, purple areas featuring dimming, and white areas experiencing both. Credit © Michala Garrison/NASA Earth Observatory

Astronomy & Telescopes, Imaging & Spectroscopy, Press Release, SETI & Technosignatures

Terrestrial Technosignatures: Satellites Capture The Glowing Pulse Of Human Civilization

by Keith CowingApril 10, 2026April 10, 2026

An analysis of data from the VIIRS DNB satellite instrument covering the years 2014 to 2022 finds that nighttime lighting is increasing globally by about two percent per year. “Although […]

Astronomy & Telescopes, Biosignatures & Paleobiology, Intelligence & Language, SETI & Technosignatures, Status Report

A TESS Test of the Hybrid Ring Strategy for Technosignature Searches Using GRB 221009A

by Keith CowingApril 9, 2026April 9, 2026

We present the first observational test of the hybrid ring strategy, a general coordinated signaling scheme proposed by Seto (2025), which provides a practical Schelling-point realization for interstellar signaling.

Scatter plots of potential candidate in frequency, drift rate and signal-to-noise ratio for each polarization channel. The color and the size for each point represent the value of SNR in log space. The green and red color bar is the frequency ranges of civil aviation and navigation satellites, respectively. The black dashed lines represent the expected drift rates for each observation date. -- astro-ph.IM

Astronomy & Telescopes, Biosignatures & Paleobiology, Comets and Asteroids, Intelligence & Language, Interstellar, Magnetic Fields, Electromagnetism, bioelectricity,, SETI & Technosignatures, Status Report

Narrowband Radio Technosignature Search Toward 3I/ATLAS With FAST

by Keith CowingMarch 21, 2026March 21, 2026

3I/ATLAS is the third confirmed interstellar object passing through the Solar System. In this work, we conduct narrowband radio technosignature search toward 3I/ATLAS using the Five-hundred-meter Aperture Spherical Telescope (FAST) […]

The Milky Way appears above Earth’s bright atmospheric glow in this Aug. 23, 2025, photograph from the International Space Station as it soared 261 miles above southern Iran at approximately 12:54 a.m. local time. The camera was configured for low light and long duration settings. -- NASA/ESA larger image

Astronomy & Telescopes, Biosignatures & Paleobiology, Imaging & Spectroscopy, Intelligence & Language, Interstellar, SETI & Technosignatures, Status Report

Broadband SETI: A New Strategy To Find Nearby Alien Civilizations

by Keith CowingMarch 10, 2026March 10, 2026

One of the most interesting questions that astronomy can hope to answer is: are we alone in our Milky Way galaxy?

Left panel: schematic of an extraterrestrial transmitter on a planet (green) within the Exo-IPM, with Rimp indicating the impact distance of the passing line of sight between Earth and the ETI transmitter from the stellar object (orange). Right panel: simplified thin-screen representation of phase perturbations in a narrowband monochromatic wave propagating through a turbulent medium, showing Doppler-shifted frequencies. Temporal variations in these perturbations lead to spectral broadening of the transmitted signal. -- The Astrophysical Journal

Astronomy & Telescopes, Biosignatures & Paleobiology, Press Release, SETI & Technosignatures, Space Weather & Heliophysics

Why SETI Might Have Been Missing Alien Signals

by Keith CowingMarch 5, 2026March 5, 2026

A new study by researchers at the SETI Institute suggests stellar “space weather” could make radio signals from extraterrestrial intelligence harder to detect. Stellar activity and plasma turbulence near a […]