Never had astronomers seen them like this. The sharp infrared eye of the James-Webb space telescope had to be pointed at them, for these nearby galaxies to finally reveal their secrets. leaving the researchers “amazed” !
It hasn’t even been a year since the James-Webb Space Telescope (JWST) returned its first scientific images. Breathtaking images. Of exceptional quality. It is precisely this quality “staggering” what’High Angular Resolution Physics in Nearby Galaxies collaboration team (Phangs), a team of over one hundred astronomersastronomershas been exploiting for a few months to better understand how some of the processes that play out on a small scale in our UniverseUniverse — the beginnings of star formation, for example — have an impact on the evolution of the largest objects in our cosmoscosmos — THE galaxiesgalaxies. They have just published no less than 21 articles on this subject!
As part of their project, the researchers are working on 19 spiral galaxies, 5 of which have already been the target of the instrument MiriMiri of the JWST — the observation instrument in theinfraredinfrared means on board the space telescope: M74M74, NGCNGC 7496, IC 5332, NGC 1365 et NGC 1433. “We see directly how theenergyenergy of the formation of young stars affects the gazgaz that surrounds them, and it is simply remarkable”comments Erik Rosolowsky, researcher at the University of Alberta (Canada), in a NASA communiqué.
What astronomers have seen at the heart of these galaxies are highly structured features. Features that the Hubble Space Telescope had never revealed, but which appear on images from the James-Webb Space Telescope. Glowing cavities of dust and huge cavernous gas bubbles that line the spiral arms of galaxies. In some regions, this network of features appears to be constructed from both individual and superimposed shells and bubbles where young stars release energy.
The effects of star formation
Until then, researchers had always come up once morest the same difficulty. The early stages of a star’s life cycle remained out of sight because the process is shrouded in cloudsclouds gas and dust. But, thanks to the powerful infrared capabilities of the JWST, they can now study how dust in the interstellar medium absorbs the lightlight forming stars and sends it back into the infrared, illuminating a complex network of gas and dust.
The specific wavelengths at which Miri observes and the near infrared cameranear infrared camera of the James-Webb space telescope, for example, provide access to emissionsemissions d’aromatic hydrocarbonsaromatic hydrocarbons polycyclic. Molecules that play an essential role in the formation of stars and planets. And it might help understand the evolution of galaxies over time.
” Thanks to the resolutionresolution from the JWST, we can, for the first time, perform a comprehensive census of star formation and inventories of interstellar bubble structures in galaxies near but beyond the Local Groupexplains Janice Lee, astronomer at NOIRLab (United States). This inventory will help us understand how star formation and its reactions impact the interstellar medium. To then give birth to another generation of stars. Or on the contrary, prevent the next generation of stars from forming”.
