The James Webb Space Telescope was built to observe some of the darkest and most distant objects in the universe. More than two years after the start of Webb’s mission, these ultra-distant objects are beginning to lead astronomers to rethink certain fundamental aspects of the universe. Webb’s detection of large, bright galaxies in the early universe could indicate an alternative mode of galaxy formation, which could lead to the disappearance of the Universe. dark matter.

An international team of astronomers used the Webb telescope to search for so-called “emission line galaxies” dating back to the first billion years of the universe. As we cataloged these early star formations, it became clear that they were much larger than theorists had predicted. This is consistent with Webb’s past observations, which regularly reveal ancient red-shifted galaxies that no one expected to be able to see, even with Webb’s keen infrared eyes.

The new work, published in the magazine Natureis centered around three “red monsters”, galaxies considerably larger and dustier than they should be. The team concluded that these galaxies would only exist if star formation occurred at a higher rate than expected. “Many processes in the evolution of galaxies tend to introduce a limiting step in the efficiency with which gas can convert into stars, but somehow these red monsters appear to have quickly avoided the most of these obstacles.” said study author Hiroko Sherwin of the University of Bath.

The most popular view of galactic formation today relies on dark matter, which we have not yet observed directly. Instead, we only see its gravitational effects on ordinary matter. Currently, most astronomers believe that galaxies form in a halo of dark matter, which helps gravitationally contain the atoms and molecules that eventually become stars and planets, but only about 20% of the gas becomes stars. This is called the Lambda cold dark matter model. However, Webb’s results suggest that the first galaxies formed much more quickly and efficiently than this model suggests.

Credit: NASA

Stars in Red Monster galaxies form twice as efficiently as low-mass galaxies of the same age. Their high dust content makes them appear red in Webb images, hence the nickname Red Monster. The team notes that these galaxies do not run counter to the standard cosmological model, but they could lead scientists to reconsider the role of dark matter.

Webb’s findings are already making waves. A separate publication In The Astrophysics Journal draws attention to the frequent appearance of great first galaxies in Webb’s observations. The team suggests it is time to consider alternatives to the Lambda cold dark matter model, and suggests modified Newtonian dynamics, or MOND. This hypothesis, first proposed in 1982, says that the small gravitational influence felt between galaxies cannot be described by Newton’s laws and must be described with a different equation.

No one yet knows where this work will lead. Although MOND explains what astronomers see with red monsters and similar galaxies, dark matter remains a better explanation for other cosmological phenomena. One thing is certain: the James Webb Space Telescope will play a major role in everything we discover.