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Comment by rob74 | Hacker News Reader

To stay at the scale of our galaxy:

> Filaments within clusters are separated from one another at perfectly equal distances — about the distance from Earth to the sun.

Does that mean that they are able to distinguish individual filaments that are "only" 1 AU apart, but ~ 25 000 light years (~1 600 000 000 AU) away from us? Because that would also be damn impressive!

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I think they messed up. I quickly scanned and couldn't find any reference to what they are talking about in the paper, but if you look at the resolutions involved it's much more likely they are talking about parsecs, which is defined as 'the distance from the sun at which 1 AU subtends a distance of 1 arcsecond' or a little over 3 light years.

Paper is here - https://arxiv.org/pdf/2201.10541.pdf

(Edit:Yes take a look at the images and scale bars on page 14)

The angular separation would be only 0.00013 arcseconds, so very impressive indeed. Hubble has an angular resolution of around 0.05 arcseconds in comparison. Radio telescopes can get better angular resolution than that using interferometry between distantly separated telescopes. Perhaps that's how they can do it.

The reported angular resolution (in the main paper: https://arxiv.org/abs/2201.10541) is 4 arcseconds. This is radio interferometry, which makes for better resolution, but it’s at a very low frequency (centered around 1.28 GHz = about 23 cm), which makes for worse resolution.

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