The Signal That Never Came Back

Name: The Signal That Never Came Back
Genre: Documentary

With no repeat, no surviving telescope, and no proven origin, the finale separates what the Wow! signal permits from what it proves.

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Transcript

Big Ear's observation window held the signal exactly 72 seconds.
Then it stopped, and the Wow! signal has never recurred.
On August 15th, 1977, Ohio State's Big Ear surveyed the radio sky.
A volunteer reviewed computer output on long paper strips. This sequence is unlike the surrounding readings.
The strong, narrowband emission was confined to one frequency channel.
Its frequency was near 1,420 megahertz, hydrogen's radio line.
Jerry Ehman circled the sequence 6EQUJ5 and wrote “Wow!” beside it.
6EQUJ5 encoded changing signal intensity, not a message.
Its peak was 30 to 31 standard deviations above background noise.
Big Ear relied on Earth's rotation to scan across the sky.
A fixed cosmic source should rise 36 seconds, peak, fall 36 seconds.
The Wow! signal matched that rise and fall, but appeared in only one of two beams.
The second beam would see it 72 seconds later. Nothing followed.
A follow-up search ran nearly 14 hours over days, finding no similar emission.
Another search found no narrow-band point source at its nominal coordinates.
Land development replaced the observatory site, destroying Big Ear.
The evidence allows intelligent life but proves no alien or terrestrial source.
Ehman remained unable to explain the signal after follow-up found no similar emission.
A 2024 study proposed a cold hydrogen cloud suddenly lit by a powerful transient source.
So was the hydrogen cloud the answer… or the start of a stranger question?

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