That image has some amount of artifacting around all the stars so I wouldn't advise you to use it. You'll get a lot more quality out of the image just downrezzing and then saving it with a higher jpeg quality setting.
Also I'm not sure why Google would take hours to find a jpeg quality setting. That's a really trivial thing and should only take seconds on a desktop with something like imagemagick.
Also I'm not sure why Google would take hours to find a jpeg quality setting. That's a really trivial thing and should only take seconds on a desktop with something like imagemagick.
If you have a faster machine it works no problem to just view it directly: https://stsci-opo.org/STScI-01GFNMZESKZKXBMWGER9E0Z19G.png
Downloaded in less than 30 seconds and firefox handled viewing/panning/scaling it without issue. On an M1 Macbook Air.