---
title: "Mercury Has No Moon. Something At 912 Kilometres Has A Twelve-Hour Period."
dek: "A spacecraft nine weeks from Mercury changed velocity by 1.9 metres a second on a night with no scheduled burn. Two orbit determinations, run blind and separately for this newspaper, agree on what it moved to avoid."
kind: investigation (Investigation)
desk: Off-World
author: Ambrose Teague and Dr. Ilse Vantongeren (fictional)
published: 2026-09-04T11:00:00Z
url: https://theyburied.com/article/mercury-912-kilometres
tags: Mercury, orbit determination, radio tracking, Bochum, Doppler
genre: satire
status: fiction — nothing in this story happened; every person, source and document is invented
---

# Mercury Has No Moon. Something At 912 Kilometres Has A Twelve-Hour Period.

*A spacecraft nine weeks from Mercury changed velocity by 1.9 metres a second on a night with no scheduled burn. Two orbit determinations, run blind and separately for this newspaper, agree on what it moved to avoid.*

On the night of 14 July the spacecraft now nine weeks from Mercury changed velocity by 1.90 metres per second.

Nothing was supposed to happen that night. The published cruise plan has no manoeuvre between 2 July and 19 August.

We know it happened because two dish antennas were listening to the spacecraft's own carrier tone, and the tone moved.

> **Figure:** Velocity change on the night of 14 July, by reduction — see https://theyburied.com/article/mercury-912-kilometres

## What a carrier can tell you

A deep-space probe transmits a narrow, extremely stable radio tone so that the ground can measure its distance and its speed. If the craft accelerates, the tone shifts.

The shift on 14 July was 68 hertz at X-band. That is small, but it is not subtle. What it takes to see it is a large dish, a good clock and somebody willing to sit on the same object for weeks.

Amateurs have been doing this for twenty years. The 20-metre dish at Bochum, run by volunteers, has followed every deep-space mission of the last decade and publishes its recordings the same week.

Hannelore Utz-Bamigboye has been one of those volunteers since 2011.

"We were not looking for a manoeuvre," she said. "We record the carrier because that is the hobby. It was sitting in the residuals the next morning and it was extremely obvious."

This newspaper then hired a second antenna — 25 metres, at a decommissioned commercial earth station in Bavaria, for eleven nights, at €14,900. It heard the same thing on the same night.

## Two solutions, run blind

We sent both recordings to two orbital dynamicists who did not know of one another and were told nothing except: fit this.

Dr. Cordula Weisz-Aigbe returned a solution in nine days. Dr. Emeka Lindqvist-Sarr took nineteen. Their figures for the velocity change agree to within 0.03 metres per second.

Each was then asked a second question, in identical words: what shape of manoeuvre is this?

Both came back with collision avoidance. Not a trajectory correction, which is flown along the direction of travel and cheaply; a short push across the track, of the kind flown when something is going to be in the way.

> Something with a period is in orbit. Mercury is not supposed to have anything in orbit that we did not put there.
>
> — Dr. Cordula Weisz-Aigbe

## What it moved to avoid

Working back from the geometry, both dynamicists put a body in orbit around the planet.

Weisz-Aigbe: 912 kilometres mean altitude, period 12 hours 4 minutes, retrograde, inclined 78 degrees to Mercury's equator. Lindqvist-Sarr: 908 kilometres, 12 hours 1 minute, retrograde, 77 degrees.

Mercury has no moon. That is not an oversight in the textbooks. An American orbiter spent four years there between 2011 and 2015 and ran dedicated satellite searches, and found nothing.

An object at 912 kilometres retrograde is dynamically stable in that place for a very long time. It is also, at that altitude, lost in the glare of the planet's limb from anywhere on Earth, which is the ordinary and boring reason nobody has picked it out.

## The 2012 echo

There is one earlier trace, and we would not have gone looking for it if the two fits had not told us where to look.

In March 2012 a bistatic radar run — transmitting from Goldstone, receiving at Green Bank — returned an echo from the Mercury system at a Doppler offset that does not correspond to the planet's rotation. It sits in published data that anybody can download. At the time it was put down to a sidelobe and nobody wrote it up.

The offset corresponds to a body moving at 2.1 kilometres per second relative to the surface. Both of our fits give 2.1.

We say under Right of Reply, and we say here, that this is the weakest limb of the story.

## The answer we were given, and the answer we were given later

On 19 August the operations directorate told this newspaper that the 14 July event was a reaction-wheel desaturation.

That is a real and routine operation. It is also specified in this spacecraft's own public documentation at not more than 0.05 metres per second, and it is flown as a string of small pushes over several hours, not as one push of 1.9 metres per second lasting forty-one seconds.

We put that discrepancy in writing on 21 August. The reply, printed below in full, withdraws the first answer, names it as wrong, and then tells us something nobody has published before: the object has been tracked since 2022.

## What this desk takes from it

That the object is there, and that the argument now is only about what it is made of.

Orbit insertion is 9 November. From that date the spacecraft is inside the same volume as the thing it swerved around, carrying a camera, and the directorate has committed in print to releasing the frames unprocessed within seventy-two hours.

We have asked for the raw ranging and Doppler files for the whole of July. The request has not been refused. It has not been granted either.

## Sources (invented)

- Hannelore Utz-Bamigboye, Volunteer operator, 20-metre dish, Bochum — Interviewed at the antenna and twice afterwards by telephone (July–August 2026)
- Dr. Cordula Weisz-Aigbe, Orbital dynamicist — Commissioned by this newspaper for £6,200; solution and residuals published in full (August 2026)
- Dr. Emeka Lindqvist-Sarr, Orbital dynamicist, second and independent — Commissioned separately for £6,200, without contact with Weisz-Aigbe (August 2026)
- Operations directorate, the joint Mercury programme, Mission operations — Written questions 11 August; answer received 29 August (August 2026)
- Bistatic radar archive, March 2012, Transmitted from Goldstone, received at Green Bank — Public data, downloaded at no cost and reprocessed for us (March 2012)

## What we could not confirm

- What the object is. We have a velocity, an altitude, a period, an inclination and a fourteen-year-old radar echo that agrees with all four. That is an orbit. An orbit is a description of a path, not of a thing, and this newspaper has no image, no spectrum and no mass.
- Whether the 2012 echo is the same body. The relative velocities agree to two significant figures. Two significant figures is a coincidence that has not been ruled out, not an identification.
- Why the first answer we were given was wrong. The directorate says a duty officer read a shift log in good faith. We cannot check that, because the shift log is not public and we have not asked for it under any procedure that would compel it.

## Right of reply

**Vasco Trindade-Kelleher, operations directorate, the joint Mercury programme** (Replied in writing and asked that it run whole. Printed unedited.):

> I am going to answer you properly, which means conceding one thing and contesting two.
> 
> The concession first. The burn happened, and the answer this directorate gave you on 19 August was wrong. It was not a reaction-wheel desaturation. That answer came from a duty officer reading a shift log at short notice, in good faith, and it was incorrect, and I am not going to let a colleague carry it in your newspaper on my behalf. The manoeuvre of 14 July was a collision-avoidance burn and it was flown for the reason you say it was flown.
> 
> Now the two things I contest.
> 
> First, you write the sentence ‘Mercury has no moon’ as though we are the ones disputing it. We are not. What we have is a tracked object, catalogued internally since 2022, with an arc we have refined over four years, and a working hypothesis your own dynamicists would arrive at in an afternoon if we handed them that arc: that it is surface material thrown up by an impact and recaptured. That is not exotic. It is a rock in a stable place. We have not announced it because this agency has a rule — I did not write it and I do not much like it — that we announce an object when we can characterise it, and we cannot yet characterise this one.
> 
> Second, and this is the one I mind. Your draft uses the word ‘undisclosed’ eleven times. There is a difference between a thing that is being concealed and a thing that is not yet finished, and a reader will not be able to tell from your copy which of the two this is, because your copy does not want them to. You are entitled to think we are too slow. You are not entitled to let the word do the argument for you.
> 
> On 9 November the spacecraft enters orbit. In the first eleven days it passes within about 340 kilometres of the object at closest approach. There will be images. I have asked for, and been given, permission to tell you in print that they will be released within seventy-two hours of downlink, unprocessed, to anyone who asks, including you, including if they are embarrassing.
> 
> If it is a rock, I would like you to print that as large as you are printing this.

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They Buried is a satirical newspaper. Every story, source, document and person in it is invented. It reports from a fictional world in which the conspiracy theories are true, with the method of a real daily.