Channel Islands : Ovni(s) jaune(s) près d'Aldernay - 23 avril 2007.

Nablator a écrit:Mais mon Stellarium n'est pas meilleur qu'un autre.

Sebastien a écrit:Vous devriez trouver pour le soleil az=206° et h=50°.

marcassite a écrit:Mais au moins c'est fiable sans bricolage.

RayanOO a écrit:1 - Un tremblement de terre dans la région a bien suivi l'observation faite et cela quatre jours plus tard.

2 - Une ancienne observation similaire à celle du 23 avril 2007 a bien eu lieu au XIXème siècle. Cette observation a aussi été suivi d'un tremblement de terre deux jours après:

Greetings Mister Martin Shough,

[...]

Because you are probably one the best specialist (if not the best) of the Channel Islands UFO case (23 April 2007) due to your impressing work with others, I modestly wanted to present you an hypothesis one our member proposed some years ago.
Of course, it is actualy a little short and not enough developed, and this more in this email because I translate French to English a thread of our French forum where our member presented this hypothesis (you have the forum link at the end of this message and you are welcome in our forum, as to post in English if you want).

It will be a great honor for us if you gimme your thoughts about this hypothesis (as to authorize me to copy paste it in our forum).

Summerize of the hypothesis proposed:

Sebastien - our member - determined that it was raining around 3 hours before the observation, and that the Sun (may have) pierced in some places. He wondered what the landing pists of Alderney and Guernesey "airports" could have to do with all this sighting.
They seem to be "perpendicular" for him to the flight and they were perhaps still wet. Fog moisture saturated the air.

With Stellarium software it seems the sun was 44 to 45° elevation at 224/226° azimuth. With the help of Google Earth, Sebastien made the following figure:
https://2img.net/r/ihimg/a/img856/4606/vueducockpit.jpg
This is Commandant Bowyer drawing :
https://2img.net/r/ihimg/a/img849/5894/croquisq.jpg

Some "3D" reconstitutions:
https://2img.net/r/ihimizer/img69/7079/upview.jpg
https://2img.net/r/ihimizer/img689/7484/startkd.jpg
https://2img.net/r/ihimizer/img818/8968/middle2uap.jpg
https://2img.net/r/ihimizer/img27/3905/endrz.jpg
Errata, in one of the picture, it is noticed 14:12z but it probably was 14:14z

General Source : https://ufo-scepticisme.forumactif.com/t2453-channel-islands-ovnis-jaunes-pres-d-aldernay-23-avril-2007

Best Regards,

Gilles Fernandez.

Hello Gilles

Thank you for your email. I very much appreciate you telling me about this idea. It is one that we didn’t think of, so i am glad to have the opportunity of discussing it. I think it’s a very interesting idea, and quite attractive :– two islands, two runways, long, thin reflectors near the direction of the sun;  two UAPs, similar direction, near the sea horizon, not moving much... yes it makes a case worth looking at.

It’s been a long time since i was immersed in this case but here are my immediate thoughts:

1)  First there is the issue of the relative bearings of the UAPs, the islands and the axis of the aircraft coordinate system.  We established that the azimuth of the LOS to UAP #2 apparently did intercept Guernsey, and Capt Bowyer confirmed to us that UAP #2 was seen against the sea, the sky and the island as its elevation varied. But the other LOS did not lie near Alderney. It was significantly to the right (west) of Alderney, which was visible at the time. In fact Capt Bowyer’s initial impression was that UAP #1 was a reflection from glasshouses on Guernsey.

Both Guernsey and Alderney were visible at the time from cruise altitude, despite being hazy. Bowyer confirmed this to us and the radio transcript records him saying it. But, as the drawing which you reproduce indicates, and as Capt Bowyer explicitly stated, both UAPs were seen to the right of the nose, during the time that Alderney lay a significant angle to the left of the nose, as proven by the radar track of the flight heading. Taking account of the crabbing angle due to winds does not decrease this discrepancy but actually increases it by a few degrees.

The radio transcript records that Capt Bowyer said “I've got the island [Alderney] visual” while looking at UAP #1 which he guessed was “off the north . . . north-north-west coast of Alderney . . . over Burhou-ish at the moment”.

This is re-emphasised a little later at 1414 when the controller asked him if both objects appeared “between yourselves and Alderney?” Bowyer:  “Negative, I think over maybe to the west of Alderney. . . .  The first one [UAP #1] is maybe closer, looks like Burhou area or beyond Burhou from me in a straight line.”

2)  The angular length of the objects could fit the airport runways – for example Guernsey’s 4800ft (1460m) runway from a distance of 35 nmi would subtend about 0.3 deg, comparable to Capt Bowyer’s estimate of the length of UAP #2 (initially about 0.25 deg). But consider the runway width. This was 148 ft (45m) and it was not being viewed perpendicular to the LOS (i.e. from vertically above, 35 nmi up) but from a very shallow depression angle ex hypothesi of less than about one degree, so the subtended angle is tiny, only a few arc seconds. Even when Bowyer was using binoculars the effective visual angle would be much narrower than the ordinary arcminute limit of resolution acuity. This means that even making very idealised assumptions the Guernsey runway would only be detectable as a vanishingly thin line.

3)  Of course if the reflection is brilliant enough then a combination of haze diffusion and ocular glare can exaggerate the apparent thickness. But in practice, the proposed reflection mechanism with the sun shining off wet tarmac is far from ideal for a brilliant reflection. To get the most efficient near specular sun reflection from a level surface needs the angle of incidence to be close to the angle of reflection to within 0.5 deg or less. If the sun was close to the horizon we could get a strong forward gloss that might help to make this bit of wet tarmac visible from 35 miles. But the sun elevation was almost 100 times the required angle.

4)  Even if the sun was well placed for specular reflection I would be uncomfortable with the idea that these strips of tarmac would be singled out for brilliant reflections. We attempted to make a similar case for the much more promising idea of specular reflections from the angled glasshouse roofs. The azimuthal geometry doesn’t work, but at least the roof slopes could have provided effective reflectors. Why would two runways on islands many miles apart be singled out for such extraordinary reflections? They may have been “wet” but so was the sea! ;-) And the Brittany lakes, which we also tried as mirage targets. And the sea or a lake can have some proportion of wave slopes at the critical angle for an efficient specular glitter. A runway cannot.

5)  Both UAPs were visually identical in detail - that is, both had the same outline and the same dark band in the same position 2/3 of the way along. The runway reflection theory should offer some explanation of this fact (control tower building at same position on both runways? – just a thought).

6)  The runway reflection theory offers no interpretation of the simultaneous observation of an elongated yellowish object in the reported approximate position of UAP #1 made on a reciprocal bearing by Capt Patterson from Blue Island 832 flying near Sark. Neither does any other good theory, I concede. Still, it would be nice.

In summary, I think this is an intriguing idea and I’m grateful to its originator and to you for sharing it.  My opinion at the moment is that it probably can’t be made to work. But please do keep me informed of progress.

Thanks again
Martin