Any ideas what would cause this?

[Thalestris24]

Hi all

Was just going through some of the subs I managed to get the other night. I happened to take just 3 x 360s subs of the Flaming Star Neb. There's no sign of the nebula on the subs ( ) but on the 2nd one 3 lights suddenly appeared and weren't present on the third sub. Am a bit puzzled as to what would cause this - I figure it must have been 3 brief flashes which appear to follow a curve? They don't seem like an airplane (but might be?) and there's no apparent trailing. Any ideas? I'm just curious.

Here are the subs in sequence (ignore the gradients and lack of colour!):

Thanks for looking!

Louise

[carastro]

Oooer.  No idea, won;t be a plane or satellite as they would show a trail at 360secs.  

Carole 

[Thalestris24]

Strange, eh? Thought I'd picked up a supernova until I noticed there were three! Must be something man-made but bright enough to produce some slight diffraction spikes.

UFO? Hee hee

[Ruud]

 It's very mysterious.

[Owmuchonomy]

What was the time of night exactly?

[Thalestris24]

What was the time of night exactly?

Hi Chris

The second sub was started at 17:55 on the 27th. The third at 18:02. I did lots of other subs of different targets either side of them but only that 2nd one had the artefacts.

Louise

Edit: it must have been one object that briefly flashed on and off. Maybe there would have been another but off-frame.

[Owmuchonomy]

Hi Louise I thought that if it is relatively soon after sunset it could be something reflective and rotating or tumbling in the atmosphere such as a weather balloon? Who knows.

[Thalestris24]

Maybe - but it would have to flash pretty briefly to not produce trailing. Maybe some sort of strobe light on an aircraft? Maybe a helicopter? It starts off quite small then gets bigger (or vice versa) over the 6 mins. Can't tell how long it was actually in view other than the max of the exposure. Oh well. Wish it could have been a supernova - that would have been cool!