Another natural question that a man has always asked of existence is whether indeed we are alone in the universe. SETI basically stands for scientific search for extraterrestrial intelligence and includes the scientific endeavor searching for evidence of intelligent life elsewhere than on Earth. With the tide of improvements in technology and increased knowledge of the cosmos, much has been achieved in SETI, but there is still so much that needs to be conquered.
SETI, or the Search for Extraterrestrial Intelligence, really began in the 1960s by starting radio signal detection programs from distant stars. The basic idea is that intelligent civilizations may well be broadcasting signals for others to receive as we do through our own radio transmissions. The Arecibo Message, beamed from Earth in 1974, was one of many attempts by humans to demonstrate their intelligence and capture the attention of extraterrestrial life. Although these efforts did not bring concrete results yet, they did lay the ground for more complex investigations.
This is arguably the biggest technological leap forward in SETI. The large-scale data analytic capabilities of the modern telescope allow it to analyze huge volumes of data in scanning the skies for the anomalous signal. In the largest scientific initiative ever undertaken in this field, the Breakthrough Listen Initiative started scanning the galaxy in 2015 using powerful radio telescopes that monitored billions of radio frequencies.
However, the search is a very complicated operation. The space involved is enormous: of course, the problems in terms of detection and interpretation are similarly immense. Any signal we might have detected can be swamped by cosmic noise due to phenomena such as pulsars and quasars. Furthermore, those signals may come in forms entirely different from what we could possibly identify. Scientists believe that machine learning will facilitate the process of data screening much better, and this increases the chances of breaking through.
Beyond radio signals, SETI is not searching for anything but optical SETI, which actually looks at the possibility of civilizations using lasers as communication tools. Researchers are examining brief, high-intensity laser pulses as signals that may represent intelligent life. As of now, these methods are in their infancy, providing room for further exploration.
Ironically, new exoplanets discovered are rekindling interest in looking again for life. Potentially habitable planets discovered within the "Goldilocks zone" or a region where conditions are right to support liquid water may be much more alive and vibrant than we have ever considered. Further missions, such as the James Webb Space Telescope, could analyze distant atmospheres for biosignatures to make our search for extraterrestrial life more meaningful.
There is increasing interest in SETI also, as high-profile projects like the Citizen Science project allow people to process their own data. That seems to indicate a wider interest in being able to know if we are alone in the universe.
Conclusion: Searching for extraterrestrial intelligence is really an interesting area of interplay between science, philosophy, and technology. Since there has been no solid evidence of intelligent life outside Earth, progress and discovery continually push the search for such. Exploring the ancient question of whether we alone in this space remains one of humanity's most important missions.
