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I just wonder if anyone could shed any light on this puzzle.

Two nights ago whilst I was out photographing the Lyrids meteor shower from the UK something else showed up on my images when I checked them the next morning. All images were 30-second exposures at ISO 2000 shot throughout the whole night with the intervalometer. It takes roughly two minutes for a satellite to pass through an image, so that's four images which you can see when viewing the images.

This started just after 01:00 and disappeared from the frame at 01:25.

Upon going through further I have a small speck starting from the top of image which continues through the image for 41 images; doing the maths, that's 20 minutes of something passing through the sky slowly.

It never continued all the way through, just slowly got darker. I was obviously set up towards the star Vega and the Lyra constellation. Any help would be greatly appreciated.

slow moving object over 20 minutes exposure

Cropped and rotated, showing broken trail:

slow moving object over 20 minutes exposure cropped and rotated, showing broken trail

uhoh
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Harvey Shelley
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    See https://heavens-above.com/AllSats.aspx for your location. – Mike G Apr 24 '20 at 17:27
  • thanks for that mike. I couldnt seem to track back earlier than 3.30am.this pass happened at just after 1am in my view and went out of vision in the frame at 1.25 am.whatevr it was was extremely slow.do you have any suggestions yourself what this may have been – Harvey Shelley Apr 24 '20 at 18:48
  • It could be a satellite in high orbit. – Mike G Apr 24 '20 at 23:20
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    I've made some small edits please check. It's probably a silly question but are those times the same in UTC? Would you estimate the speed at about 1 degree per minute, or could you come up with a better number? Could you also mention the focal length and aperture of your lens? As mentioned in the other comment there are some slow moving satellites in high orbits but they would have to be quite high to move so slowly and therefore far away and dim. It could also plausibly be a near earth asteroid (since they're larger and potentially brighter but that would be something we'd read about. – uhoh Apr 25 '20 at 04:37
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    Also, you posted this question at 2020-04-24 16:35 UTC (Friday) and you say it was "two nights ago". Does that mean that you first recorded the object at about 2020-04-23 01:00 UTC i.e. Wednesday night/Thursday morning? – uhoh Apr 25 '20 at 04:40
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    hi there, yes your dates are correct and time.In terms of degrees a minute I am not to sure. I shot on a canon 5dmk 2, so a full frame camera at 24mm and 2.8 f. Last night I made a composite of the 41 images to see the final pass. Whatever it appears to be it does show very visible curvature, im not sure what that would mean, im guessing just that its higher up. On my 24mm image it still only goes through around a third of the image from top to bottom. Its starts from slightly to the left of Zeta Draconis and goes out of sight at next to HR 7187. Hope this can help you and other people – Harvey Shelley Apr 25 '20 at 08:22
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    Iv just been trying to find some more research and came across this. Does anyone think this may be what I have caught ? Any suggestions or help would be much appreciated.https://www.virtualtelescope.eu/2020/04/24/near-earth-asteroid-2020-hx3-very-close-encounter-a-exceptional-image-24-apr-2020/ – Harvey Shelley Apr 25 '20 at 21:25
  • @HarveyShelley thanks for your reply, I'll look into this further... btw if you have a look at How do comment @replies work? (found in metaFAQ) you can see that if you add the @ followed by a user name (keep an eye out for the autocomplete option) then that user will receive a notification of your reply. I found your comments now only because I happened to stop by, and they are very helpful! – uhoh Apr 26 '20 at 02:55
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    @uhoh I had a look back on sky safari and other apps around this time to see if anything passed through and nothing at all passed through, would just be good for someone to be able to identify what this was. – Harvey Shelley Apr 28 '20 at 19:50
  • @HarveyShelley thanks for the ping and the reminder! Okay I'll get on it today. – uhoh Apr 28 '20 at 21:20
  • @uhoh also had a final image which I cant yet attach on here. thanks – Harvey Shelley Apr 29 '20 at 07:15
  • @HarveyShelley wow that would be incredibly useful to see! If you can leave a comment with a link to say imgur.com or some other media site, someone here can add it to your question perhaps. You don't have access to this yet? https://i.stack.imgur.com/xgu4V.png – uhoh Apr 29 '20 at 08:40
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    @uhoh . so going through your instructions I managed to attach a low res image of it, in the top original post! So if you zoom in on the image you can see where the breaks where between the 30 sec exposures and how also there is curvature in the streak whereas all satellites iv photod before travel dead straight and go through the image frame roughly in 2 minutes. let me know if you cant see this. thanks – Harvey Shelley Apr 29 '20 at 12:24
  • @HarveyShelley you may find this interesting if you'd like to get exact RA/Dec or Alt/Az from all of these stars: How (the heck) does Astrometry.net work? However it's hard to imagine that those star trails represent 20 minutes of exposure! In 20 minutes the stars should move about 5 degrees relative to foreground and in this photo the stars and the foreground (roof and shadow of tree) are both clear meaning you didn't track for 20 minutes. This looks more like a short meteor photo with a chopping wheel to measure the speed of the meteor. – uhoh Apr 29 '20 at 13:14
  • @uhoh . So I understand what you are saying about no star trials, correct there is no movement in the stars. I used the first starting image as the base and then layered the additional 40 images only painting in the streak throughout the rest of the sequence until it gradually faded away, – Harvey Shelley Apr 29 '20 at 13:40
  • I think I understand in principle what you are saying but wow it's hard to imagine how one does that in practice and still get such a nice looking seamless and artifact-less composite image. btw there is also Photography SE with an active astrophotography community. This question is certainly okay here but you may enjoy checking out that site as well. – uhoh Apr 29 '20 at 13:52
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    @uhoh ill have a look at what you suggested and see if anyone else can help. I see I should probably be extending this convo in chat anyway. So being restricted to the garden, I had to position where lyra would pass over my garden to capture initially the meteors.I wasn't using a trakker hence there should have been star trails in twenty minutes if one exposure. I basically opened each image one by one in photoshop masking them as layers only painting the streak back to the image, hence no movement in stars. choice of what you thought it was, what would you suggest or could you not say – Harvey Shelley Apr 29 '20 at 14:11

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