James Webb telescope keeps finding galaxies that shouldn't exist

Fiona Jackson
The Daily Mail
Mon, 17 Apr 2023 16:27 UTC

© NASA/ESA/I Labbe

Six galaxies (pictured) spotted by JWST are far too massive to be the age their data suggests they are, which is between 500 and 700 million years old

NASA's James Webb Space Telescope (JWST) keeps spotting galaxies that are too big to exist, scientists have claimed.

Six of these star clusters are far too massive to be the age their data suggests they are, which is between 500 and 700 million years old. This means that, unless the data has been analysed incorrectly, there is still something fundamental to learn about how galaxies formed after the Big Bang.

'If the masses are right, then we are in uncharted territory,' said the study's author, Dr Mike Boylan-Kolchin from the University of Texas at Austin.

One theory is that the universe expanded much more quickly after the Big Bang than is currently assumed.

The $10 billion JWST, which sent back its first official photos in July last year, is designed to detect light from the earliest stars and galaxies.The further away an object is, the further back in time it is looking, because it takes longer for the light to reach its 21 foot-long (6 m) mirror.

It is the world's biggest and most powerful orbital space telescope, and is capable of peering back 100 to 200 million years after the Big Bang.

In February, scientists at the Swinburne University of Technology in Australia analysed the data it had collected on six galaxies.

© NASA/ESA/I. Labbe

In February, scientists analysed the data it had collected on six galaxies. They estimated the age of the first one they looked at to be about 13.8 billion years old, but the light JWST had detected had taken 13 billion years to reach it.

They estimated the age of the first one they looked at to be about 13.8 billion years old, but the light JWST had detected had taken 13 billion years to reach it.This meant that what they were observing was a picture of how it looked when the universe was just 700 million years old - barely 5 per cent of its current age. However, this picture also showed it was made up of 100 billion stars - the same amount as the present-day Milky Way, which had 13 billion more years to grow.

It was a similar story for the five other galaxies, where they contained way more stars than would be predicted for a cluster of their age.

For a follow-up study, published in Nature Astronomy last week, Dr Boylan-Kolchin 'stress tested' these results against the 'ΛCDM cosmological model'.

This is a framework for understanding the role of dark energy (Λ) and cold dark matter (CDM) in shaping the universe's evolution.

Galaxies form when clouds of gas collapse under their own gravity, becoming increasingly dense and hot, and eventually forming stars.

But some of this gas can be lost, either because it is ejected during the star formation process, or stripped away by an exterior force, like a nearby supernova.

Graph that shows the relative amount of atoms (y axis) contained in galaxies with at least a certain mass (M*) of stars (x axis). Three galaxies detected by the JWST (black square) appear to be using up a much larger number available gas atoms for stars than would be expected

'We typically see a maximum of 10 per cent of gas converted into stars,' said Dr Boylan-Kolchin.

However, for these six galaxies to have grown as big as they have in the time they have existed, they must have been converting nearly 100 per cent of their available gas into stars.

Dr Boylan-Kolchin added: 'While 100 per cent conversion of gas into stars is technically right at the edge of what is theoretically possible, it's really the case that this would require something to be very different from what we expect.'

This means that the ΛCDM model, which has been relied upon by cosmologists since the late 1990s, may not be totally correct.

Dr Boylan-Kolchin said. 'We'll require something very new about galaxy formation or a modification to cosmology.

'One of the most extreme possibilities is that the universe was expanding faster shortly after the Big Bang than we predict, which might require new forces and particles.'

Therefore, it is possible that the model needs to be altered to take these new, faster galaxy formation processes into account.

It could also be the case that there was more matter available to the start of the universe for star and galaxy formation, which the model should also account for.

But before scientists jump to change their fundamental approach to cosmology, the data from the JWST needs to be confirmed as correct.

It may be the case that supermassive black holes could have heated up the gas surrounding the galaxies, making them appear larger than they are.

The light that the JWST detected may also not have originated as far back as 13 billion years, meaning that it may actually show the galaxies at more advanced ages.

As light travels across expanding space, its wavelength is stretched and frequency reduced, through what is known as 'redshift'.

The magnitude of the redshift allows scientists to calculate when the light was emitted from a star, but it can be impacted by dust and give the wrong age.

It is hoped further study will reveal if this is the case.

Dr Boylan-Kolchin wrote: 'If analysis of JWST data continues to reveal the presence of strikingly massive galaxies at very early cosmic epochs, more exciting surprises lie ahead for the fields of galaxy formation and cosmology.'

Comment: The JWST goes from strength to strength. And to think Congress nearly killed the project. From PhysOrg:

Shining like a brilliant beacon amidst a sea of galaxies, Arp 220 lights up the night sky in this view from NASA's James Webb Space Telescope. Actually two spiral galaxies in the process of merging, Arp 220 glows brightest in infrared light, making it an ideal target for Webb. It is an ultra-luminous infrared galaxy (ULIRG) with a luminosity of more than a trillion suns. In comparison, our Milky Way galaxy has a much more modest luminosity of about ten billion suns.

Located 250 million light-years away in the constellation of Serpens, the Serpent, Arp 220 is the 220th object in Halton Arp's Atlas of Peculiar Galaxies. It is the nearest ULIRG and the brightest of the three galactic mergers closest to Earth.

The collision of the two spiral galaxies began about 700 million years ago. It sparked an enormous burst of star formation. About 200 huge star clusters reside in a packed, dusty region about 5,000 light-years across (about 5 percent of the Milky Way's diameter). The amount of gas in this tiny region is equal to all of the gas in the entire Milky Way galaxy.

Previous radio telescope observations revealed about 100 supernova remnants in an area of less than 500 light-years. NASA's Hubble Space Telescope uncovered the cores of the parent galaxies 1,200 light-years apart. Each of the cores has a rotating, star-forming ring blasting out the dazzling infrared light so apparent in this Webb view. This glaring light creates diffraction spikes — the starburst feature that dominates this image.

© NASA, ESA, CSA, STScI Image processing: Alyssa Pagan (STScI)

Image of Arp 220 captured by Webb’s Near-Infrared Camera (NIRCam) and Mid-Infrared Instrument (MIRI), with compass arrows, scale bar, and color key for reference. The north and east compass arrows show the orientation of the image on the sky.

The north and east compass arrows show the orientation of the image on the sky. Note that the relationship between north and east on the sky (as seen from below) is flipped relative to direction arrows on a map of the ground (as seen from above). The scale bar is labeled in light-years, which is the distance that light travels in one Earth-year. (It takes 18,000 years for light to travel a distance equal to the length of the bar.) One light-year is equal to about 5.88 trillion miles or 9.46 trillion kilometers. The field of view shown in this image is approximately 120,000 light-years across. This image shows invisible infrared wavelengths of light that have been translated into visible-light colors. The color key shows which filters were used when collecting the light. The color of each filter name is the visible-light color used to represent the infrared light that passes through that filter.

On the outskirts of this merger, Webb reveals faint tidal tails, or material drawn off the galaxies by gravity, represented in blue — evidence of the galactic dance that is occurring. Organic material represented in reddish-orange appears in streams and filaments across Arp 220.

Webb viewed Arp 220 with its Near-Infrared Camera (NIRCam) and Mid-Infrared Instrument (MIRI).