• Skua@kbin.earth
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    10 days ago

    I know this is absolutely not the point of this, but for some reason this prompted me to try to get a sense of the resolution the JWST is providing here. Here is the original image without our infinite otter overlord. It’s a small part of NGC 3324, which looks like this. If you look at the right hand side of that photo, about in the centre vertically, you’ll see the section that the post’s image shows. It’s rotated 90 degrees between the zoomed in and zoomed out images.

    NGC 3324 has an apparent dimension of 11 arc minutes, or 0.183 degrees. So if you imagine a ball that’s 10cm across and another one that’s 20cm across but twice as far away, they’ll have the same apparent dimension. If you imagine a triangle drawn between the observer and the two outside points of the subject, the apparent dimension is the angle of the corner of the triangle at the observer.

    So if imagine holding an object at arm’s length, say 0.8 m away, how big would that object have to be to have an apparent dimension of 11 arcminutes? About 5 mm. The entire photo - the zoomed out one - is the equivalent of holding a grain of rice at arm’s length. And then we get this zoomed in one still showing crazy detail on just a tiny fraction of that