The James Webb Space Telescope (JWST) has been in operation for just three years, but it’s already revolutionized our understanding of the cosmos. Launched on a day that marks its third anniversary, JWST has explored the Solar System, studied distant planets’ atmospheres, and probed the farthest depths to find the first stars and galaxies formed in the Universe.
One of the most significant discoveries made by JWST is the existence of extremely bright, massive, and blue galaxies that are unlike any seen before. These galaxies, found at a time when the Universe was only 300 million years old, are thought to have formed quickly due to efficient star formation. However, their unusual characteristics – being incredibly bright, massive, and blue without any dust – remain a puzzle.
JWST has also discovered unusual chemical features in early galaxies, including significant amounts of nitrogen and metals that don’t fit our current models. This suggests that there were processes at play in the early Universe we still don’t fully understand.
The telescope’s capabilities have allowed it to peer deep into the cosmos, discovering faint galaxies and pushing the limits of our knowledge on galaxy formation. The discovery of small galaxies that may have played a crucial role in ending the cosmic “dark ages” after the Big Bang is particularly significant.
Furthermore, JWST has revealed an abundance of “little red dots” – compact red colour sources of unknown origin. These objects exhibit unusual properties, including bright hydrogen gas emitting light at incredible speeds, characteristic of a feeding frenzy around a supermassive black hole. The true nature of these galaxies remains a mystery, sparking debate among scientists.
Finally, JWST has uncovered extremely dead corpses: massive galaxies that formed in the first 700 million years of cosmic history, which our current models cannot explain. These discoveries have revealed shortcomings in our current understanding of the Universe and leave us eager to refine our models and uncover more secrets.
As JWST continues its journey, it will undoubtedly shed more light on the mysteries of the early Universe, providing scientists with a wealth of new information to analyze and build upon.
Source: https://www.sciencealert.com/3-years-after-jwsts-launch-heres-what-it-has-taught-us-about-the-universe