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81 points janandonly | 1 comments | | HN request time: 0s | source
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fprog ◴[] No.43372696[source]
An alternate hypothesis which seems equally interesting, albeit for different reasons, is at the end of the article:

> Another explanation for why the JWST may have seen an overrepresentation of galaxies rotating in one direction is that the Milky Way's own rotation could have caused it.

> Previously, scientists had considered the speed of our galaxy's rotation to be too slow to have a non-negligible impact on observations made by the JWST.

> “If that is indeed the case, we will need to re-calibrate our distance measurements for the deep universe," Shamir concluded. "The re-calibration of distance measurements can also explain several other unsolved questions in cosmology such as the differences in the expansion rates of the universe and the large galaxies that according to the existing distance measurements are expected to be older than the universe itself."

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perihelions ◴[] No.43372859[source]
I'm utterly confused what's going on. They're measuring galaxies' rotations by looking at images of the subset that are spiral galaxies, and checking which direction the arms spiral. They describe their image processing algorithm in their paper [0]. (it's around figure 3)

How can local movement of stars within the Milky Way affect which way spiral galaxy arms are pointing?

[0] https://academic.oup.com/mnras/article/538/1/76/8019798.

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Mertax ◴[] No.43372933[source]
There is no absolute direction for a galaxy’s spin—it’s always relative to the observer’s perspective.

So I’d suspect they’re saying time and distance would need to be factored in rather than just looking at static images relative to our position today since our own spin may have caused a particular galaxy to appear to have been spinning in a different direction at another point in space-time

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1. ◴[] No.43373593[source]