Double trail

[jambouk]

Whilst processing subs for a star trail I noticed a satellite trail in one of the subs, which I then realised was a double trail, but with one leading trail and one lagging one. The same effect is on the adjacent subs (always the top trail first, then the bottom trail), and it took about 50 seconds to cross about 45 degrees of sky in a west to east direction just under Polaris.

It doesn't look like an aircraft, but what is it? Is it just an aircraft?

I think the peak brightness (cropped area below) was at 22:35 on 26.4.15 (the minutes will be correct, but it could have been 23:35 as I'm not sure I've changed the time on my camera), from Nottingham.

James

[Demonperformer]

That is a weird effect.  If it was on just a single sub, I would be tempted to say that it was two unrelated phenomena, because one trail fades to the left and the other fades to the right.  So I can't see it being a plane.  But if it is repeated on adjacent subs ... does it occur on all of the subs taken? If so, my only guess would be an artifact in the imaging train ... a filter that has got a couple of scratches on it, for example.

I will be interested to see what it finally turns out to be.

[jambouk]

It is on about 4 subs, and it travels east to west, but this is the brightest it gets, it is VERY faint on the other subs, and the lines remain parallel, but staggered. I think it has to be something man made, but not sure if a satellite or aircraft. The subs were 10 seconds each. Not an artifact of my kit as it doesn't exist on the hundreds of other subs.

James

[Demonperformer]

Sorry, I'm obviously being rather dense, but I don't understand "it travels east to west". To me it looks as if the two trails are travelling in opposite directions. The upper one is faint on the left and gets brighter into the middle and cuts off abruptly just right of centre and the lower one is faint on the right and gets brighter into the middle and cuts off abruptly just left of centre. It looks almost as if they are a 180-degree rotation of each other.

If it was just the one sub, I would be inclined towards two satellites travelling in opposite directions and a chance shot of them crossing, but that cannot be if the same pattern is repeated (albeit faintly) on adjacent subs.

This one really has me beat atm.

[jambouk]

The exact same pattern, with the lines staggered, appears in the previous sub or two and in the subsequent sub or two, but the position of it moves across the sky, actually originating from behind my house (in the west) and disapearing towards the east (gets too faint before it has chance to hide behind some trees).

#

James

[jambouk]

It's an aircraft. Just found some aircraft trails in the same series (below) and for whatever reason there is no red light in the trail, and there is no real flash of light, they just alternate. Case closed.