JWST image
So, what are we looking at in this image?
https://www.nasa.gov/sites/default/files/thumbnails/image/main_image_deep_field_smacs0723-5mb.jpg
The image is stunning, a huge leap over Hubble (comparison at https://imgsli.com/MTE2Mjc3 ) and really showcases JWST.
The main target is a cluster of galaxies called SMACS 0723 (or more completely J0723.3-7327). Here's a preprint about the cluster: https://arxiv.org/abs/2207.05007
0723 is very far away, NASA says 4.6 billion light years. Astronomers measure these big distances as redshift, z. Our galaxy is z=0, 0743 is at z=1.38 to z=1.45
I think all of the spiky bois in the image are foreground stars (in our galaxy), so just a few hundred thousand light years at most.
The really interesting bit, and the reason for imaging 0723, is the stuff that's even farther away -- the gravitationally lensed galaxies, with their light smeared into crescents and whorls as it travels past 0723 towards us. We could see some of this with Hubble, but the added sensitivity with JWST is just spectacular. Those galaxies will be at z=6 and even deeper.
JWST image
@eqe i was gonna ask about the "smearing" of some of the galaxies. thought it may be gravitational lensing but I'm not familiar with the numbers there, so I thought the effect would be less dramatic--if I'm seeing this properly, it seems like the whole image is at least slightly warped in this way
