Recovered Signal 14

Note

This is a summary release. The body of the original is retained pending review. What follows is what the Disclosure Board judged could be said in 2016 and re-affirmed, unchanged, in 2023.

Finding

During reprocessing of archival propagation survey data — undertaken to validate a new pipeline, not to look for anything — a structured emission was recovered from material collected between ██ and ██.

The emission is:

• Terrestrial. Bearing was resolved from a baseline and is consistent with a fixed ground source. There is no ambiguity about this and no basis for any other reading of it.
• Narrowband, at an allocation withheld here.
• Periodic, with an envelope repeating every 1,270.4 seconds.
• Structured within the envelope, in a manner described in the withheld body. The structure is not random and is not an artefact of the recovery pipeline; it survives reprocessing under three independent implementations.

On the period

The envelope period matches the residual period reported in SEN-81-017 to four significant figures.

The institution has no account of why. The following are stated plainly to prevent them being inferred:

1. The two observations are separated by more than thirty years.
2. They involve entirely different instruments, at different times, measuring different physical quantities. One is a clock comparison residual. The other is a received emission.
3. No common equipment, no common personnel, and no common processing code links them. This was checked specifically and at length.
4. The 1981 record was not consulted during the 2014 recovery. The correspondence was noticed afterwards, by a reviewer who had read both, and who has said since that she assumed it was a coincidence and expected to be told so.

She was not told so. It remains unexplained.

What this is not

The institution states the following without qualification, because the alternative is that someone else will state something worse on our behalf:

• This is a terrestrial signal. It is not of non-human origin, and nothing in the record supports that reading.
• It is not evidence of anything being transmitted to anyone.
• It has no established connection to any event, programme or organisation outside this institution.
• It is not dangerous, and it is not doing anything. It is a recording of a radio emission that happens to have a period we have seen before.

The entry is classified RESTRICTED because of the provenance of the survey material and the third party it identifies. It is not classified because the signal is alarming. It is classified because publishing it in full would identify someone who did not agree to be identified.

Present status

Open. Assigned to Directorate III as a standing item, reviewed each March.

The reviewing officer’s note from the most recent review is reproduced in full, with the Board’s permission:

Eleven years. We have excluded every mechanism we can construct and we are left with a number that appears twice. I would rather record that we do not know than construct an account that sounds like knowing.