James Webb space telescope: Spiral galaxies have "grown up" far too early
Galaxies like our Milky Way form a kind of bar when they become internally stable and "grow up", so to speak. This probably happened earlier than expected.
Artistic representation of the Milky Way with a bar highlighted in yellow.
(Bild: NASA/JPL-Caltech/ESO/R. Hurt)
The James Webb Space Telescope has once again delivered data that pose problems for current theories on the development of the early universe. As the University of Durham in the UK explains, a research team has used observations from the state-of-the-art instrument to discover that spiral and similar galaxies took on stable forms much earlier after the Big Bang than previously thought. The team attributes this to visible bars at their centers, which regulate the rate of star formation by pushing interstellar gas into the heart of galaxies like our Milky Way. When they are formed, a galaxy is considered "grown up". In images of almost 400 galaxies, these bars were discovered much more frequently than previously expected.
Stable conditions much too early
(Bild: Zoe Le Conte)
The research group led by doctoral student Zoe Le Conte analyzed 357 galaxies from the period of around two to six billion years after the Big Bang. This means that the James Webb Space Telescope (JWST) has seen about a billion years further back than its predecessor Hubble. 20 percent of the objects had such bars - three to four times as many as in earlier analyses. This means that the more powerful instrument was able to detect galactic bar formation much earlier and surprised the research group. It was actually expected that the universe was more turbulent at this time and experienced many more collisions of galaxies that were unable to stabilize. The prevailing theories on galaxy formation would therefore probably have to be revised.
The work presented in the Monthly Notices of the Royal Astronomical Society is now just the latest in a growing series of observations from the space telescope that do not fit our current understanding of the early universe. For example, since it began operating almost two years ago, it has been continuously finding galaxies that were many earlier, much larger, than previously thought possible. A few weeks ago, a galaxy collision was also discovered, which must have been an enormous coincidence if the theories are correct. The oldest black hole discovered by the JWST is also far too massive. The apparently too early bar formation only fits into the picture.
(mho)