Stabilised footage from winter solstice night over London—lens flare or actual object?

Found this footage on an old hard drive from December 2017. Shot it from my flat in Hackney during the solstice night - was just filming the sky because the light pollution was surprisingly low that evening (was a bit cloudy which helped).

Didn't notice anything odd at the time. But looking back at it now with better video software, there's a definite object that moves in a way that doesn't match weather balloons or aircraft. It's in the frame for about 8 seconds, moves non-linearly, and the brightness changes are odd.

I've tried to stabilise it and enhance the footage. It's low quality because the original was shot on a phone, but I'm wondering if anyone with better equipment wants to take a look? I've ruled out:

- Lens flare (movement doesn't track with camera angle)
- Aircraft (wrong trajectory, too silent based on ambient sound)
- Weather balloon (movement patterns, speed changes)
- Chinese lantern (brightness variation rules this out)

What am I looking at?

Upload it to the file sharing section and I'll run it through some analysis software I've got. Don't want to commit to conclusions without seeing the original file. Compression can introduce artefacts that look like movement, so I want to check the raw data.

The solstice timing is interesting though. If it's real movement and not compression artefacts, then you've got activity during an astronomical event, which fits patterns other people have documented.

Just going to say it: 8 seconds is a very short window and stabilisation software can introduce movement patterns that weren't in the original. Before you get too invested, what does the original unstabilised footage look like? Does the object move the same way, or does the 'movement' appear once you've applied digital stabilisation?

The fact that you noticed it during low light pollution is key. Most urban UFO reports are dismissed as reflections or distant lights, but if you've got low background light and low ambient noise (you recorded sound apparently?) then you've got decent documentation. Definitely share the raw file.

This is exactly the kind of civilian documentation we need more of. Professional telescopes and military equipment are one thing, but regular people with phones capturing incidental footage is how we build datasets. Even if it turns out to be mundane, it's useful data.

@CursedCipher443 raises a fair point on stabilisation artefacts - worth knowing what software processed this. Warp stabiliser in Premiere can genuinely manufacture apparent motion in stationary light sources.

That said, the solstice date is worth noting. There's documented correlation between significant astronomical alignments and increased UAP activity going back decades - not just fringe claims, proper catalogued cases.

What camera and focal length were you shooting with? A wide-angle lens on a handheld will behave very differently to something with optical zoom. Chromatic aberration around the object's edges would tell us a lot about whether we're looking at an internal lens phenomenon or something external to the optical system entirely.

If you can share the raw unprocessed file, the EXIF data alone would answer several questions immediately.