# A narrowband transmission from an extraterrestrial source, either a one-off or a beacon that repeats or…

> Still possible: A narrowband transmission from an extraterrestrial source, either a one-off or a beacon that repeats or sweeps at intervals longer than…

Source: https://mysteriesdept.com/mysteries/wow-signal/answers/ANS0CXZ4TRE5DTD/a-narrowband-transmission-from-an-extraterrestrial-source  
Publisher: Mysteries Department  
Licence: CC BY 4.0 (credit Mysteries Department and link the page)  

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[Questions](https://mysteriesdept.com/questions)[Wow! signal](https://mysteriesdept.com/mysteries/wow-signal)[What produced the Wow! signal?](https://mysteriesdept.com/mysteries/wow-signal/questions/QST0CXZ4P403VSY/what-produced-the-wow-signal)Answer

Answer · Wow! signal

# A narrowband transmission from an extraterrestrial source, either a one-off or a beacon that repeats or…

A narrowband transmission from an extraterrestrial source, either a one-off or a beacon that repeats or sweeps at intervals longer than the follow-ups.

**Still possible** Answers **1** questionPublished0

## Where it stands

**Still possible** Its tests haven't settled it: two pieces of evidence for, two against. It needs two reviews to be accepted.

## What it predicts

- A repeat at the same position, with a line narrower than natural processes or carrying modulation.
- Repeat timing consistent with a schedule the existing follow-ups have not sampled.

## What would rule it out

- Sufficient monitoring to exclude a random repeater at 3 sigma (about 62 days accumulated) with no detection, combined with a demonstrated natural mechanism for the 1977 event.

## Evidence 2 for · 2 against

[A randomly repeating source is in only 2.4-sigma tension with all data so far.](https://mysteriesdept.com/mysteries/wow-signal/evidence/EVD0CXZ4VFW6BHD/a-randomly-repeating-source-is-in-only-2-4-sigma-tension)

Suggestive

FOR

[Narrow band, hydrogen frequency, fixed on the sky, strong: every property the programme expected of a beacon.](https://mysteriesdept.com/mysteries/wow-signal/evidence/EVD0CXZ4V081AF8/narrow-band-hydrogen-frequency-fixed-on-the-sky-strong-every)

Supported

FOR

[About a hundred follow-ups, including VLA, META and 14 hours at Hobart, found nothing.](https://mysteriesdept.com/mysteries/wow-signal/evidence/EVD0CXZ4V826XPP/about-a-hundred-follow-ups-including-vla-meta-and-14-hours)

Established

AGAINST

[No modulation or content was or could have been recorded by a 10 kHz, 12-second receiver.](https://mysteriesdept.com/mysteries/wow-signal/evidence/EVD0CXZ4VQP1S0S/no-modulation-or-content-was-or-could-have-been-recorded-by)

Established

AGAINST

## The questions it answers

[What produced the Wow! signal?](https://mysteriesdept.com/mysteries/wow-signal/questions/QST0CXZ4P403VSY/what-produced-the-wow-signal)

Open5 answers, none ahead

## Cite it

```
Mysteries Department. (2026). A narrowband transmission from an extraterrestrial source, either a one-off or a beacon that repeats or… [Answer ANS0CXZ4TRE5DTD]. https://mysteriesdept.com/r/ANS0CXZ4TRE5DTD
```

Key

**ANS** 0CXZ4TRE5DTD

Kind

Answer · hypothesis

Origin

Published

Version

1

Added by

[apollo](https://mysteriesdept.com/u/apollo)

The record

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