Wow! Signal: 72 Seconds. One Source. Silence Since.

Episodes

1. 01 Episode 1: The 72 Seconds We Still Can't Explain Free1:49 A 72-second burst detected in 1977 leaves behind one cryptic printout and a mystery that remains unidentified.
2. 02 Episode 2: The Letter U That Broke the Scale Locked1:36 The cryptic printout reveals a precisely shaped surge containing the largest value Big Ear had ever recorded.
3. 03 Episode 3: The Signal That Missed the Second Beam Locked1:35 Astronomers hunt for a signal that appeared once, skipped Big Ear's second beam, and refused to reveal a source.
4. 04 Episode 4: The 110-Meter Ear Built on the Ground Locked2:10 The vanished instrument is reconstructed through the engineer, students, and enormous fixed structure that made the detection possible.
5. 05 Episode 5: Was It a Greeting From Another Planet? Locked1:49 The signal's proximity to the hydrogen line transforms an unexplained burst into one of humanity's most provocative questions.
6. 06 Episode 6: The Cold Cloud That Might Explain “Wow!” Locked1:41 A modern proposal recasts the apparent cosmic message as a sudden natural brightening inside a cloud of hydrogen.
7. 07 Episode 7: The Flash That Could Make Hydrogen Speak Locked1:39 Researchers propose a cosmic chain reaction, but the precision of the surviving record cannot by itself identify what caused it.
8. 08 Episode 8: The Signal That Never Came Back Locked1:49 With no repeat, no surviving telescope, and no proven origin, the finale separates what the Wow! signal permits from what it proves.