We compare the images of the James Webb Telescope with those of its predecessor, Hubble

Have you ever seen star dust? The 32nd edition of Star Nights will take place on August 5, 6 and 7. Opportunity to view the stars with the naked eye, binoculars or even using a telescope. But none of them will be as accurate as the James Webb Space Telescope (JWST), the most powerful in the world, which makes it possible to observe space in many details. One of its latest images, released by NASA on Tuesday, August 2, makes it possible to distinguish star dust and star-forming regions in the Cartwheel Galaxy.

The James Webb Telescope, the result of cooperation between the US, European and Canadian space agencies, should make it possible to see more in space. Thus, we go back further into the past in the hope of understanding the formation of the universe. A comparison with its predecessor, the Hubble telescope, which has already taken similar shots, allows us to appreciate this technological leap. Franceinfo asked astrophysicist Eric Lagadec, a stardust specialist and president of the French Society for Astronomy and Astrophysics, to compare James Webb and Hubble images.

cart wheel galaxy

The Cartwheel Galaxy is located 500 million light-years from Earth. Two space telescopes have been able to immortalize it, but the shot by James Webb shows much more detail than that of the Hubble telescope.

In the image provided by Hubble in 2010, we guessed without seeing it accurately, in the black areas within the large blue circle, dust, as a result of a collision between the Cartwell wheel galaxy and another galaxy. Compression of dust and gas leads to the formation of new stars.Eric Lagadec explains.

The James Webb image shows regions of dense gas and dust more clearly. “With infrared, we can now spot dust. Sometimes we can even see through it, but it depends on the conditions and characteristics of that dust,” Eric Lagadec analyzes. Finally, from the almost black background of the Hubble image, we pass to a background decorated with dozens of distant galaxies, which James Webb made visible.

The Southern Ring Nebula

Its scientific name is “NGC 3132”, but it is rather called the “Australian Ring Nebula” or the “Eight Fragments Nebula”. This expanding gas cloud is located at a distance of about 2,000 light-years. So it is one of the closest known planetary nebulae to Earth, According to NASA.

The central star visible in the center in the Hubble image, released in 1998, is dying. “As a result, it shrinks and heats up. This will stir up the gas everywhere and give the different colors that Hubble picks up,” Eric Lagadec describes.

In the James Webb image, the red parts and the farther parts are actually cooler gases, because the star and dust have already expelled them. It is invisible with Hubble, but JWST’s infrared technology makes it possible to represent this gas.

Carina Nebula

You might think that you can see steep mountains in these pictures. It is actually one end of the Carina Nebula. These charming shapes, called “cosmic cliffs,” lie at the edge of a giant gas cavity within NGC 3324, spotted about 7,600 light-years away. On the James Web site.

Shades of yellow and red in the two images once again illustrate regions of dust and gas, where new stars are forming, Eric Lagadec explains.

James Webb’s photo is so accurate that it allows you to observe a lot of details. The places with more or less dust stand out in the image, such as the layers of a mountain. “this is a nice picture!” Eric Lagadec, who admits to making it his mobile wallpaper, rejoices.

Stephan quintet

Stephan’s Quintet is a group of five galaxies located in the constellation Pegasus. The interaction of these galaxies creates star-forming regions, as Eric Lagadec deciphers. “With Hubble, we see more stars and hot gases, with more dust and cold gases with Webb,” Describes an astrophysicist.

The image below is the largest to date by James Webb, and covers about a fifth of the moon’s diameter. It contains more than 150 million pixels and is built from nearly 1,000 separate image files, According to the telescope website.

What is impressive above all is the amount of galaxies visible in the distance. Quantities of celestial bodies that have not yet been discovered.