Cosmic Silence: 70,000 Stars Without a Signal ⚡ экспресс
A search for narrowband radio signals was carried out using the 100-meter Green Bank Telescope in the L-band (1.15–1.73 GHz). Emission from more than 70,000 stars within ~9 arcminutes of the beam was processed. The pipeline’s efficiency for detecting signals with frequency drift rates of ±9 Hz/s was 94–99%. All 100 million candidates turned out to be anthropogenic: 99.5% were automatically discarded, and 0.5% visually inspected. A strict upper limit was derived: with 95% confidence, the fraction of stars within 20,000 light-years hosting a detectable transmitter (EIRP > 5×10¹⁶ W) is less than 6.3×10⁻⁵. The most interesting signals were uploaded to a citizen science platform with the participation of over 40,000 volunteers. AI is used for automatic radio frequency interference removal and improved detection. The UCLA SETI project involves about 200 undergraduates and 20 graduate students.
Searching for extraterrestrial signals is like trying to hear a whisper at a roaring stadium. The Green Bank Telescope listened to 70,000 stars, but 100 million bursts turned out to be earthly noise — from phones, satellites, microwave ovens. Automation filtered out almost everything, and the rest was checked by 40,000 volunteers. There's no alien whisper.
Silence itself is important. The transmitter we were looking for is tens of times more powerful than all the energy humanity has ever emitted. We'd have noticed it with ease. But there are fewer than six such 'horns' per 100,000 stars within 20,000 light-years. The stadium is empty.
🎯 The total energy of all human radio broadcasts ever made is less than the power of a single strong transmitter sought by this telescope.
🎬 In the movie 'Contact,' radio telescopes pick up an extraterrestrial signal. The real search, so far, is more like an attempt to hear silence.