Hours of image processing work were devoted to each of the five full-color images from the James Webb Space Telescope released by NASA this week.
Why it’s important: Through its photos, the JWST, which captures light at wavelengths that the human eye cannot see, will change the way the public and scientists understand the history of the universe.
Where it is: JWST looks at the universe with infrared light, allowing it to cut dust to see the intimate details of star formation and even the dim light of some of the first galaxies to form. more than 13 billion years ago.
- “Biologically, we just don’t have the ability, even if we floated next to these objects, to see them the way Hubble or Webb can see them,” Joe DePasquale, a working image processor, tells Axios with JWST.
How it works: When photos taken by the JWST’s huge mirror are transmitted to Earth, they basically look black, DePasquale says.
- “Each pixel in the image has over 65,000 different shades of gray that it can be,” he said, adding that “the universe is very faint,” so most of the interesting parts of a JWST image are “buried in the darkest regions of the image.”
- The imaging equipment must then illuminate the darker parts of the image to show the details hidden inside the pixels without oversaturating the brightest fragments of the image, which may be galaxy cores or stars. bright.
The JWST is so sensitive that it is able to differentiate between different bands of infrared light in the same way that our eyes can see different bands of optical light, which we perceive as colors.
- Because of this sensitivity, imaging equipment is able to sort long and short wavelengths of infrared light, allowing them to filter the image through various colors in a scientifically sound way.
- The human eye perceives the longest wavelengths of optical light as red, so color replaces the longest wavelengths of infrared light. Blue is used for shorter wavelengths and the other colors of the rainbow are in between.
- “If you had infrared eyes that were sensitive to that light, that might be what you would see,” Klaus Pontoppidan, a JWST project scientist, said during a press conference.