A Search for Narrowband Technosignatures from LTT 3780 with the Allen Telescope Array and the Karl G. Jansky Very Large Array
The Astrophysical Journal Letters American Astronomical Society 1006:2 (2026) l56
Abstract:
The LTT 3780 system hosts two known exoplanets—LTT 3780 b, a rocky super-Earth, and LTT 3780 c, a temperate sub-Neptune—orbiting a nearby M dwarf on opposite sides of the radius valley. LTT 3780 c has been proposed as a candidate Hycean world, making the system an important target for astrobiological investigation, particularly in light of recent JWST atmospheric observations. Although biosignature and technosignature searches both seek evidence of life beyond Earth, these approaches have historically been pursued independently. Well-characterized exoplanet systems provide an opportunity to combine these complementary search strategies. In this work, we conducted radio technosignature observations of the LTT 3780 system using both the Allen Telescope Array and the Karl G. Jansky Very Large Array (VLA). The two facilities provide complementary observational capabilities, with the ATA optimized for wide-band multibeam postprocessing analyses and the VLA enabling high-sensitivity real-time interferometric searches. Across ∼30 hr of total observing time, we searched for narrowband Doppler-drifting signals in the frequency range ∼1–10 GHz. After applying comprehensive radio-frequency interference mitigation and multibeam consistency tests, no candidate signals consistent with astrophysical or technosignature origins were identified. We place minimum detectable effective isotropic radiated power limits of 4.7 × 1012–3.6 × 1013 W across the observed bands and facilities. Although no technosignatures were detected, this work demonstrates how complementary observation and analysis strategies can be applied to exoplanets of astrobiological interest and serves as a pathfinder for future combined biosignature and technosignature investigations.A Search for Radio Technosignatures from Interstellar Object 3I/ATLAS with the Allen Telescope Array
The Astronomical Journal American Astronomical Society 172:1 (2026) 1
Abstract:
In 2025 July, the third-ever interstellar object, 3I/ATLAS, was discovered on its ingress into the solar system. Similar to the NASA Voyager missions sent in 1977, science probes by extraterrestrial life (“artifact technosignatures”) could be sent to explore other stellar systems like our own. In this campaign, we used the SETI Institute’s Allen Telescope Array to observe 3I/ATLAS from 1–9 GHz. We detected nearly 74 million narrowband hits in 7.25 hr of data using the newly developed search pipeline bliss. We then blanked hits by frequency and drift rate to mitigate radio frequency interference in our dataset, narrowing the dataset down to ∼2 million hits. These hits were further filtered by the localization code NBeamAnalysis, and the remaining 211 hits were visually inspected in the time-frequency domain. We did not find any signals worthy of additional follow-up. Accounting for the Doppler drift correction and given the nondetection, we are able to set an effective isotropic radiated power upper limit of 10–110 W on radio technosignatures from 3I/ATLAS across the frequency and drift rate ranges covered by our survey.
A Search for Radio Technosignatures from Interstellar Object 3I/ATLAS with the Allen Telescope Array
The Astronomical Journal 172:1 (2026)
Abstract:
In 2025 July, the third-ever interstellar object, 3I/ATLAS, was discovered on its ingress into the solar system. Similar to the NASA Voyager missions sent in 1977, science probes by extraterrestrial life (“artifact technosignatures”) could be sent to explore other stellar systems like our own. In this campaign, we used the SETI Institute’s Allen Telescope Array to observe 3I/ATLAS from 1–9 GHz. We detected nearly 74 million narrowband hits in 7.25 hr of data using the newly developed search pipeline bliss. We then blanked hits by frequency and drift rate to mitigate radio frequency interference in our dataset, narrowing the dataset down to ∼2 million hits. These hits were further filtered by the localization code NBeamAnalysis, and the remaining 211 hits were visually inspected in the time-frequency domain. We did not find any signals worthy of additional follow-up. Accounting for the Doppler drift correction and given the nondetection, we are able to set an effective isotropic radiated power upper limit of 10–110 W on radio technosignatures from 3I/ATLAS across the frequency and drift rate ranges covered by our survey.
Silent Speech Recognition with Wearable Magnetometers
bioRxiv preprint 2025.08:04.668236 (2025)
Abstract:
Next-generation human-computer interaction (HCI) is moving towards more seamless, intuitive,
and personal modes of communication, redefining how we interact with technology and one another.
Within this landscape, silent speech recognition (SSR) offers a powerful new interaction paradigm,
enabling hands-free, private interaction while supporting individuals with speech impairments and
enabling communication in noisy or sensitive environments. Recent advances in miniaturized sensors and artificial intelligence (AI) have accelerated the development of more sophisticated wearable
SSR systems, driven by growing demand for effortless and accessible communication. Although
electrophysiological (ExG) modalities, particularly electromyography (EMG), have dominated early
efforts in developing wearable SSR, critical challenges remain. Limited generalizability across
users, sensor-skin interface issues, and difficulties with the comfort of use are all current roadblocks
to reliable, high-fidelity signals in a wearable form factor. We propose that magnetometers offer
a promising alternative to ExG and have the potential to unlock more robust, generalizable, and
user-friendly SSR systems. We demonstrate that magnetometers embedded in a headphone form
factor achieve a per-user SSR accuracy of 86%, significantly outperforming previously reported
state-of-the-art wearable headphones combining ExG and inertial measurement units (IMUs). In
addition, we show that wearable magnetometry enables generalization across individuals for SSR.
Extending beyond headphones, we also introduce a necklace form factor with magnetometers that
is capable of decoding both silent and overt speech in ambient conditions, further showcasing the
versatility of magnetometers across different wearable designs in real-world conditions.
and personal modes of communication, redefining how we interact with technology and one another.
Within this landscape, silent speech recognition (SSR) offers a powerful new interaction paradigm,
enabling hands-free, private interaction while supporting individuals with speech impairments and
enabling communication in noisy or sensitive environments. Recent advances in miniaturized sensors and artificial intelligence (AI) have accelerated the development of more sophisticated wearable
SSR systems, driven by growing demand for effortless and accessible communication. Although
electrophysiological (ExG) modalities, particularly electromyography (EMG), have dominated early
efforts in developing wearable SSR, critical challenges remain. Limited generalizability across
users, sensor-skin interface issues, and difficulties with the comfort of use are all current roadblocks
to reliable, high-fidelity signals in a wearable form factor. We propose that magnetometers offer
a promising alternative to ExG and have the potential to unlock more robust, generalizable, and
user-friendly SSR systems. We demonstrate that magnetometers embedded in a headphone form
factor achieve a per-user SSR accuracy of 86%, significantly outperforming previously reported
state-of-the-art wearable headphones combining ExG and inertial measurement units (IMUs). In
addition, we show that wearable magnetometry enables generalization across individuals for SSR.
Extending beyond headphones, we also introduce a necklace form factor with magnetometers that
is capable of decoding both silent and overt speech in ambient conditions, further showcasing the
versatility of magnetometers across different wearable designs in real-world conditions.