What was the target of JWST's first deep field image?

JWST's first deep field image targeted the galaxy cluster SMACS 0723. Officially designated SMACS J0723.3−7327, the cluster lies about 4 billion light-years away in the southern constellation Volans.

The target was chosen because the cluster's immense mass bends and magnifies light from galaxies behind it, an effect called gravitational lensing. That natural magnification helps Webb detect extremely faint and distant galaxies that would otherwise be much harder to observe. The image was made with Webb's Near-Infrared Camera, or NIRCam, using observations at several infrared wavelengths.

NASA released the image publicly in July 2022, calling it Webb's First Deep Field. It showed thousands of galaxies in a patch of sky roughly comparable in apparent size to a grain of sand held at arm's length. A frequent mix-up is naming one of Webb's other early image subjects, such as the Carina Nebula or the Southern Ring Nebula; those were part of the initial image release, but SMACS 0723 was the deep-field target.