Humanity’s fascination with the possibility of extraterrestrial life has endured for centuries. As we look up at the night sky, our curiosity is piqued by the vast unknown—questions surrounding the existence of life elsewhere in the universe continue to capture our collective imagination. For decades, the idea of discovering signals from extraterrestrial civilizations has sparked both hope and skepticism. In 1984, the Search for Extraterrestrial Intelligence (SETI) became a formal scientific endeavor, dedicated to detecting potential signals of alien origin.
However, despite numerous efforts and technological advancements, SETI has yet to yield concrete evidence of extraterrestrial life. Still, the search continues with undiminished zeal. Recently, SETI researchers have employed a cutting-edge technology to reanalyze data from over a million cosmic objects in the hopes of detecting any signs of life or technological activity beyond Earth. The results, however, remain elusive.
But did this extensive search provide any new insights into our search for life in the cosmos?
COSMIC: The Cutting-Edge Technology Behind SETI’s Latest Search
At the heart of this most recent effort is COSMIC—a sophisticated data-processing system designed to assist in the search for technosignatures, the telltale signals that could point to extraterrestrial civilizations. COSMIC stands for Commensal Open-Source Multimode Interferometer Cluster, and it’s a powerful signal-processing algorithm that works in conjunction with the Karl G. Jansky Very Large Array (VLA), one of the world’s most advanced radio telescopes.
The VLA itself is a highly versatile array consisting of 28 radio dishes, each spanning 25 meters across. These dishes are mounted on movable tracks, which allows for fine-tuning of their position to optimize the angular resolution and sensitivity of the array. This design makes the VLA capable of observing a range of astronomical phenomena, including quasars, pulsars, supernova remnants, and even black holes. Importantly, the VLA is also capable of scanning vast regions of space in search of radio transmissions, which may suggest the presence of technologically advanced civilizations.
The VLA is currently engaged in an ambitious project called the VLA Sky Survey (VLASS). This long-term effort aims to monitor the entire visible sky for transient radio signals—rapidly changing signals that could be associated with some cosmic event. As part of this ongoing survey, COSMIC is being used to analyze data in real-time, autonomously searching for signals that fit the criteria for artificial or technological origins.
As technology advances, so too must our methods for processing the enormous volumes of data generated by modern astronomy. With millions of data points flooding in from observatories like the VLA, automated algorithms such as COSMIC are essential for sifting through and identifying potential technosignatures among the noise of naturally occurring cosmic phenomena.
Navigating the Data Deluge: The Role of COSMIC in SETI’s Search
One of the key challenges facing modern astronomy, and SETI in particular, is the sheer volume of data that is generated. Observatories like the VLA produce vast amounts of data, much of which is too complex and too large to be manually reviewed by astronomers alone. To address this challenge, scientists rely on algorithms and automated processing systems to efficiently comb through data and identify meaningful signals.
COSMIC plays a crucial role in this endeavor by analyzing data from the VLA’s VLASS project. As the VLA scans the skies, COSMIC sifts through the radio signals emitted by over 950,000 cosmic objects in search of patterns that could indicate the presence of extraterrestrial technology. The system looks for signals that exhibit specific characteristics, such as narrowband signals and Doppler shifts—features that are often associated with artificial signals. These signals are notably different from the broad-spectrum emissions typically generated by natural astrophysical sources.
For a signal to be considered a technosignature, it needs to meet certain conditions. It must be narrowband (a narrow range of frequencies) and exhibit changes over time, such as the Doppler effect, which occurs when the frequency of the signal shifts as an object moves toward or away from the observer. Even with these criteria in place, however, the search space remains vast, and millions of signals could potentially be examined.
Thus, COSMIC applies an array of assumptions and algorithms to narrow down the potential technosignatures from the noise. Signals that do not meet these criteria are discarded, while those that show promise are flagged for further investigation. Each potential technosignature is cataloged in a database, accompanied by small data snippets, called postage stamps, for further analysis.
Searching the Cosmos: No Technosignatures Found (Yet)
Despite the sophistication of COSMIC and its ability to scan an impressive number of cosmic objects, the recent search yielded no definitive technosignatures. COSMIC processed data from over 950 million cosmic sources, but the search for extraterrestrial signals came up empty.
However, this does not mean that the search was in vain. On the contrary, the results of this latest study represent an important step forward in the development of SETI research. Chenoa Tremblay, the lead author of the study, emphasized that this search is only the beginning, marking a successful test of the COSMIC system’s capabilities.
For the current study, researchers focused on a subset of the data, specifically 30 minutes of observation from the VLA, during which they focused on 511 stars cataloged in the Gaia catalog. After rigorous analysis, no potential technosignatures were identified, but the researchers were able to test the system’s functionality in a controlled environment.
Although no signals were found, the COSMIC system demonstrated its potential to efficiently handle large-scale data searches, processing nearly 1 million sources of data. This accomplishment is significant in itself, as it proves the system’s ability to autonomously analyze vast amounts of data and filter out false positives, paving the way for faster, more accurate searches in the future.
What Have We Learned?
So, what have we learned from this latest search for alien signals? Although no technosignatures were detected, the study offers valuable insights into the state of modern SETI research. First and foremost, it demonstrates that the search for extraterrestrial life is becoming increasingly automated and efficient.
As COSMIC continues to process the VLA’s data, future searches will be able to target an even greater number of cosmic objects, with faster and more refined algorithms to sift through the data. The sheer volume of data generated by modern astronomical observations requires a new approach to sorting and analyzing signals, and COSMIC provides just such a method.
The fact that no technosignatures were found in this study should not be discouraging. Rather, it is an important milestone in the ongoing search for life in the cosmos. The search continues, and the methods used in this research will only improve as technology advances.
A Step Toward the Future: The Ongoing Quest for Extraterrestrial Life
In conclusion, the recent effort by SETI researchers to search for extraterrestrial technosignatures using the COSMIC system represents a significant leap forward in our quest to answer one of humanity’s oldest and most profound questions: Are we alone in the universe?
While the search may not have yielded immediate results, it highlights the importance of continuing to refine our search methods, and it offers hope that one day we may detect signals from distant civilizations. The tools we have at our disposal, like COSMIC, are rapidly advancing, allowing us to scan the skies with greater precision and efficiency.
As our technology improves and our understanding of the cosmos deepens, we may one day receive the long-awaited signal that proves we are not alone in the universe. Until then, the search for technosignatures continues, and the quest to understand our place in the cosmos is as important as ever.
Reference: Chenoa D. Tremblay et al, COSMIC’s Large-Scale Search for Technosignatures during the VLA sky Survey: Survey Description and First Results, arXiv (2025). DOI: 10.48550/arxiv.2501.17997