An official website of the United States government
We describe archival observations and analysis of the HD 110067 planetary system using the Green Bank Telescope (GBT) as part of the Breakthrough Listen search for technosignatures. The star hosts six sub-Neptune planets in resonant orbits, and we tune the drift rate range of our search to match the properties of the system derived by Luque et al. Our observations cover frequencies from 1 to 11.2 GHz, using the GBT’s L, S, C, and X-band receivers, to an equivalent isotropic radiated power limit of ∼3 × 10^12 W. No technosignatures were found, but this unusual system remains an interesting target for future technosignature searches.
more »
« less
A VERITAS/Breakthrough Listen Search for Optical Technosignatures
Abstract The Breakthrough Listen Initiative is conducting a program using multiple telescopes around the world to search for “technosignatures”: artificial transmitters of extraterrestrial origin from beyond our solar system. The Very Energetic Radiation Imaging Telescope Array System (VERITAS) Collaboration joined this program in 2018 and provides the capability to search for one particular technosignature: optical pulses of a few nanoseconds in duration detectable over interstellar distances. We report here on the analysis and results of dedicated VERITAS observations of Breakthrough Listen targets conducted in 2019 and 2020 and of archival VERITAS data collected since 2012. Thirty hours of dedicated observations of 136 targets and 249 archival observations of 140 targets were analyzed and did not reveal any signals consistent with a technosignature. The results are used to place limits on the fraction of stars hosting transmitting civilizations. We also discuss the minimum pulse sensitivity of our observations and present VERITAS observations of CALIOP: a space-based pulsed laser on board the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations. The detection of these pulses with VERITAS, using the analysis techniques developed for our technosignature search, allows a test of our analysis efficiency and serves as an important proof of principle.
more »
« less
- Award ID(s):
- 2209437 1913552 2110737 2310028 2011361 2110497 1914579 2200857 2111531 2310158 2012916 2110974 2011420
- PAR ID:
- 10437546
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- DOI PREFIX: 10.3847
- Date Published:
- Journal Name:
- The Astronomical Journal
- Volume:
- 166
- Issue:
- 3
- ISSN:
- 0004-6256
- Format(s):
- Medium: X Size: Article No. 84
- Size(s):
- Article No. 84
- Sponsoring Org:
- National Science Foundation
More Like this
-
-
Abstract The Breakthrough Listen search for intelligent life is, to date, the most extensive technosignature search of nearby celestial objects. We present a radio technosignature search of the centers of 97 nearby galaxies, observed by Breakthrough Listen at the Robert C. Byrd Green Bank Telescope. We performed a narrowband Doppler drift search using theturboSETIpipeline with a minimum signal-to-noise parameter threshold of 10, across a drift rate range of ±4 Hz s−1, with a spectral resolution of 3 Hz and a time resolution of ∼18.25 s. We removed radio frequency interference (RFI) by using an on-source/off-source cadence pattern of six observations and discarding signals with Doppler drift rates of 0. We assess factors affecting the sensitivity of the Breakthrough Listen data reduction and search pipeline using signal injection and recovery techniques and apply new methods for the investigation of the RFI environment. We present results in four frequency bands covering 1–11 GHz, and place constraints on the presence of transmitters with equivalent isotropic radiated power on the order of 1026W, corresponding to the theoretical power consumption of Kardashev Type II civilizations.more » « less
-
Abstract The Breakthrough Listen (BL) Initiative, as part of its larger mission, is performing the most thorough technosignature search of nearby stars. Additionally, BL is collaborating with scientists working on NASA’s Transiting Exoplanet Survey Satellite (TESS) to examine TESS Targets of Interest (TOIs) for technosignatures. Here, we present a 1–11 GHz radio technosignature search of 61 TESS TOIs that were in transit during their BL observation at the Robert C. Byrd Green Bank Telescope. We performed a narrowband Doppler drift search with a minimum S/N threshold of 10 across a drift rate range of ±4 Hz s−1with a resolution of 3 Hz. We removed radio frequency interference by comparing signals across cadences of target sources. After interference removal, there are no remaining events in our survey, and therefore no technosignature signals of interest detected in this work. This null result implies that atL,S,C, andXbands, fewer than 52%, 20%, 16%, and 15%, respectively, of TESS TOIs possess a transmitter with an equivalent isotropic radiated power greater than a few times 1014W.more » « less
-
Abstract The search for extraterrestrial intelligence at radio frequencies has focused on spatial filtering as a primary discriminant from terrestrial interference. Individual search campaigns further choose targets or frequencies based on criteria that theoretically maximize the likelihood of detection, serving as high-level filters for interesting targets. Most filters for technosignatures do not rely on intrinsic signal properties, as the radio-frequency interference (RFI) environment is difficult to characterize. In B. Brzycki et al. (2023), we proposed that the effects of interstellar medium (ISM) scintillation on narrowband technosignatures may be detectable under certain conditions. In this work, we perform a dedicated survey for scintillated technosignatures toward the Galactic center and Galactic plane at theCband (3.95–8.0 GHz) using the Robert C. Byrd Green Bank Telescope (GBT) as part of the Breakthrough Listen program. We conduct a Doppler drift search and directional filter to identify potential candidates and analyze results for evidence of scintillation. We characterize theC-band RFI environment at the GBT across multiple observing sessions spread over months and detect RFI signals with confounding scintillation-like intensity modulation. We do not find evidence of putative narrowband transmitters with drift rates between ±10 Hz s−1toward the Galactic center, ISM-scintillated or otherwise, above an equivalent isotropic radiated power of 1.9 × 1017W up to 8.5 kpc.more » « less
-
A growing avenue for determining the prevalence of life beyond Earth is to search for “technosignatures” from extraterrestrial intelligences/agents. Technosignatures require significant energy to be visible across interstellar space and thus intentional signals might be concentrated in frequency, in time, or in space, to be found in mutually obvious places. Therefore, it could be advantageous to search for technosignatures in parts of parameter space that are mutually derivable to an observer on Earth and a distant transmitter. In this work, we used theL-band (1.1–1.9 GHz) receiver on the Robert C. Byrd Green Bank Telescope to perform the first technosignature search presynchronized with exoplanet transits, covering 12 Kepler systems. We used the Breakthrough Listen turboSETI pipeline to flag narrowband hits (∼3 Hz) using a maximum drift rate of ±614.4 Hz s−1and a signal-to-noise threshold of 5—the pipeline returned ∼3.4 × 105apparently-localized features. Visual inspection by a team of citizen scientists ruled out 99.6% of them. Further analysis found two signals of interest that warrant follow up, but no technosignatures. If the signals of interest are not redetected in future work, it will imply that the 12 targets in the search are not producing transit-aligned signals from 1.1 to 1.9 GHz with transmitter powers >60 times that of the former Arecibo radar. This search debuts a range of innovative technosignature techniques: citizen science vetting of potential signals of interest, a sensitivity-aware search out to extremely high drift rates, a more flexible method of analyzing on-off cadences, and an extremely low signal-to-noise threshold.more » « less
