The James Webb captures an extraordinary new galaxy photo

The James Webb Space Telescope has trained its lens on the Chariot Wheel, offering a new look at this galaxy already scanned by Hubble.

NASA had promised that the new darling of world astronomy would literally put stars in the public eye. And since President Joe Biden unveiled his first images on July 12, the James Webb Space Telescope hasn’t stopped!

He has already graced us with sumptuous shots, including scientifically invaluable and aesthetically appealing shots of galaxies. We can for example cite his images Stephan’s Quintet, or NGC 628 and 7496 which were presented more recently.

The Webb pushes the limits of Hubble (again)

He returns today with a new image of another of the most photogenic objects in the cosmos. This is ESO 350-40, better known by the nickname “Trolley wheel“, accompanied by her two usual companions.

This object is located about 500 million light-years from Earth, in the constellation Sculptor. Its very regular appearance and its ideal orientation make it a prime target for astronomers and a feast for the eyes. But photographing it is not easy.

The Cartwheel Galaxy as seen by Hubble. ©ESA/Hubble & NASA

And for good reason: it is shrouded in a thick veil of dust that tends to obscure the view of telescopes. Even the venerable Hubble, which has already drawn the portrait several times, had great difficulty in discerning the most interesting details; the photos were already fabulous, but still far from scientifically satisfactory.

But the James Webb, for his part, does not have to bother with this constraint; his ” eye piercing who observes in the infrared (Hubble operates in the visible and the ultraviolet) allows him to see through the dust. As often in recent weeks, it therefore had no trouble capturing the most precise images of this galaxy to date.

The consequence of a great cosmic pile-up

We find this beautiful object in the shape of a cart wheel, as its name suggests. This very particular structure is due to a cataclysmic collision between two separate galaxies. The shock wave led to the appearance of two almost concentric rings, “ a bit like the ripples of a pond in which you throw a stone “, according to NASA.

The first, in the center, was formed directly on impact. It is extremely bright, and for good reason: there is an immense amount of superheated dust and “clusters” of relatively young and above all gigantic stars.

In the second, the landscape is quite different. It has been continuously expanding for almost half a billion years, and this dynamic is at the origin of many fascinating phenomena. As its diameter increases, the ring captures large amounts of “fresh” gas; the ideal substrate for creating new stars. This area is therefore a real stellar nursery where stars are born at a very high rate.

This image was captured using Webb’s Mid-Infrared Instrument (MIRI). © NASA, ESA, CSA, STScI, Webb ERO Production Team

The Chariot Wheel as NASA has never seen it

And these juvenile stars, the JWST has not lost a crumb thanks to the incredible precision of its instruments. On the first image captured using the NIRCam (Near-Infrared Camera), the researchers were able to distinguish many clusters of stars. All of these were largely out of Hubble’s reach.

If the second image is also different, it is because it was made using another tool. Here, the Mid-Infrared Instrument (MIRI) was used. Its primary objective is not to locate stars; he is rather interested in the dust that resides there. Its properties and distribution play a fundamental role in the dynamics of any galaxy.

Here, NASA was able to determine that certain regions were rich in hydrocarbons and silica dust. According to the institution, these materials are mainly present in rings and ” rays of the wheel. Very vulgarly, we can therefore assimilate this dust to the skeleton of the galaxy.

The other important piece of information that emerges from Webb’s observations is that the galaxy is apparently in a transition phase. The researchers believe that it was a rather ordinary spiral galaxy before the famous collision, much like our Milky Way; on the other hand, they do not yet know how this transformation will end.

And unfortunately, neither the James Webb nor humanity will still be there to witness this galactic moult; it will still last for tens of millions of years. But until then, all this fresh data will already allow researchers to refine their models. These observations were indeed full of interesting details on the interactions between galaxies as well as on their life cycle. And on our side, we just have to wait wisely while waiting for the Webb to come back and put stars – or even entire galaxies – in our eyes!

High quality images are available on the NASA website.

Leave a Comment