James Webb telescope delivers ‘historic’ first image of the universe

12 Jul 2022

Known as Webb’s First Deep Field, this image is of a galaxy cluster called SMACS 0723, with never before seen detail. Image: NASA/ESA/CSA/STScI

The first James Webb image shows tiny, faint structures of distant galaxies that have never been seen before, including star clusters and diffuse features.

After a long period of anticipation, the first colour image from the James Webb Space Telescope has been released, with more to come later today (12 July).

The image shows the galaxy cluster SMACS 0723 as it appeared 4.6bn years ago. The combined mass of this galaxy cluster acts as a gravitational lens, magnifying more distant galaxies behind it.

The deepest infrared image of our universe yet also features distant galaxies, with faint structures that have never been seen before such as star clusters and diffuse features.

Despite the immense detail in the image, NASA said this slice of the universe covers a patch of sky that is approximately the size of a grain of sand held at arm’s length by someone on the ground.

The image was unveiled at a White House event, with US president Joe Biden describing the moment as “historic” and “hard to even fathom”.

The detail on the image is made possible thanks to advanced instruments on the James Webb Space Telescope, the largest and most powerful space observatory ever built. A successor to the Hubble Space Telescope, its mission is to solve mysteries in the solar system, look to distant worlds around other stars and probe the origins of our universe.

Researchers will soon delve into the data behind these images to learn more about the galaxies’ masses, ages, histories and compositions.

Last week, NASA scientists released an engineering test image from the observatory, which had a “rough-around-the-edges” quality and was not optimised to be a science observation. That test image was taken by Webb’s Fine Guidance Sensor, which enables accurate science measurements and imaging with precision pointing.

The latest image was taken by the Near-Infrared Camera (NIRCam), Webb’s primary camera that simultaneously images the cosmos in two different infrared ranges.

The image is a composite made from 12.5 hours of images at different wavelengths, achieving depths at infrared wavelengths beyond the Hubble Space Telescope’s deepest fields, which took weeks.

10 things you need to know direct to your inbox every weekday. Sign up for the Daily Brief, Silicon Republic’s digest of essential sci-tech news.

Leigh Mc Gowran is a journalist with Silicon Republic