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I've circled them in this edit:

Source: https://commons.m.wikimedia.org/wiki/File:New_Horizons_Approach_to_Arrokoth.ogv

Note, this has generated frames, see the source. The twinkling stars are regular though, almost taking turns to twinkle.

I know it is sped up, are those variable stars, that vary that much regularly over the course of hours and days? If so wow, how many stars are like that?

Are there any good videos that show the sky in time lapse demonstrating what it would look like to see the stars twinkle like that?

Rabbi Kaii
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  • Very cool! Different but slightly related (and not the answer) Which are stars and which are noise in this comet photo? When it approached the exposure times were much shorter, so the stars didn't streak or creep. If one chooses playback speed of 0.25 in YouTube they do interesting things! I'm wondering if some frames of the video are interpolated and zoomed to make the growth of the size of the asteroid smooth in the final video. – uhoh Mar 24 '23 at 12:40
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    I hear that. And very interested thank you. I will try to make a GIF of the stars later. They flash very regularly, and are changing position with everything else, seems real. Would like a direct analysis. – Rabbi Kaii Mar 24 '23 at 12:56

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I followed the link and viewed the video there expanding the window size. The video is quite low resolution and the stars in that area were ‘twinkling’ because they were passing from one pixel to another in the CCD camera. Others throughout the view but they weren’t as noticeable as these, not sure why that was, but it was all due to the large pixels in relation to the star points.

Pogo
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  • There's no way the camera for this mission would have a pixel spacing (or for that matter, dead area between pixels) so large compared to the diffraction-limited images that they could "fall through the cracks" between pixels and cause twinkling. This is uninformed speculation. Welcome to Stack Exchange!* SE is unlike most other sites, answers need to support their assertions with authoritative citations and/or references and/or calculations. These images are taken by LORRI – uhoh Jan 21 '24 at 04:07
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    which uses the Teledyne e2V CCD47-20 Back Illuminated NIMO Frame-Transfer High Performance CCD Sensor with 13 micron pixels and 100% active area because it's backside-illuminated. With a 20.8 cm aperture and 263 cm effective focal length, Rayleigh criteria diffraction limit at 550 nm is a little over half-pixel at 8.5 microns, so sometimes a star is mostly on a single pixel, and sometimes it's split across two, but with 100% active area via backside illumination *there be no twinkling!* – uhoh Jan 21 '24 at 04:14
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    Maybe whoever made this page took out a very small area of the original screen size expanding the size of that view and the pixels along with it, or something in the processing. The video didn't go full screen, but, it did get bigger than the embedded one on the page. I could see the pixels on the video and the blinking stars were just moving from one pixel to another. But, I don't think it indicated any type of variability in the stars themselves. – Pogo Jan 21 '24 at 04:47
  • I see two "twinklers" only, and they are almost the same distance from the center of the zoom but have very different "twinkling frequencies". There are plenty of variable stars out there, in fact it's hard to find a field of view that doesn't have some. The time lapse nature of this image sequence makes periods of hours or days easy to see. I don't think there's any need to speculate about exotic processing phenomenon when variable stars are so likely to be the explanation. – uhoh Jan 21 '24 at 05:03
  • See Table 2 in Variable stars across the observational HR diagram Something like 2-3% of stars are periodic variable. – uhoh Jan 21 '24 at 05:06