This image of galaxy cluster SMACS 0723, known as Webb’s First Deep Field, is rich in detail.Thousands of galaxies, including the faintest infrared objects ever observed, have appeared in Webb’s view for the first time. This sliver of the vast universe takes up about the size of a grain of sand held at arm’s length by someone on the ground.
This deep field, captured by Webb’s Near-Infrared Camera (NIRCam), is a composite of images taken at different wavelengths over the course of 12.5 hours, achieving depths in the infrared beyond the Hubble Space Telescope’s deepest fields, which took weeks.
The image depicts the 4.6 billion-year-old galaxy cluster SMACS 0723.
This galaxy cluster’s combined mass acts as a gravitational lens, magnifying much more distant galaxies behind it. Webb’s NIRCam has brought those distant galaxies into sharp focus, revealing previously unseen structures such as star clusters and diffuse features. Researchers will soon learn more about the galaxies’ masses, ages, histories, and compositions as Webb searches for the universe’s earliest galaxies.
This is one of the telescope’s first full-color images. The full suite will be made available on Tuesday, July 12, at 10:30 a.m. EDT, during a live NASA TV broadcast.
