A new high-resolution map of distant galaxies may help scientists understand a mysterious invisible substance that helps hold the universe together.
The ordinary matter all around us — stars, planets and people — makes up just 5% of the universe. For decades, researchers have hoped to demystify what’s known as dark matter, a material that comprises just over a quarter of our universe. Another equally mysterious force called dark energy makes up the rest.
Dark matter doesn’t absorb or give off light so scientists can’t study it directly. But they can observe how its gravity warps and bends the star stuff around it — for example, the light from distant galaxies. By studying these distortions across large swathes of the universe, scientists can get closer to unmasking dark matter and its various hiding places.
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The latest map, created with images from NASA’s James Webb Space Telescope, is the most detailed yet over such a large patch of sky. The Webb telescope identified nearly 800,000 galaxies, some of which were detected for the first time, NASA said.
The map has twice the resolution of previous attempts using the Hubble Space Telescope and captures hundreds of thousands of galaxies over the past 10 billion years.
“Now, we can see everything more clearly,” said study author Diana Scognamiglio with NASA’s Jet Propulsion Laboratory.
The latest map, published Monday in the journal Nature Astronomy, includes information on new galaxy clusters and the strands of dark matter that connect them. Piece by piece, these structures help form the skeleton of the universe. Scientists can study this map to see how dark matter has clumped up over billions of years.
Dark matter doesn’t have much of an impact on your midday lunch order or your nightly bedtime ritual. But it silently passes through your body all the time and has shaped the universe.
“Wherever we see a big cluster of thousands of galaxies, we also see an equally massive amount of dark matter in the same place. And when we see a thin string of regular matter connecting two of those clusters, we see a string of dark matter as well,” said astrophysicist Richard Massey, a coauthor of the study.
As humans, we’re naturally curious to know more about where we come from and that story can’t be told without dark matter, said astrophysicist Rutuparna Das with the Harvard-Smithsonian Center for Astrophysics.
“Our home is the universe and we want to understand what the nature of it is,” said Das, who was not involved with the new study.
Earlier this month, a team of researchers discovered a new type of astronomical object dubbed “Cloud-9” that NASA described as a “starless, gas-rich dark-matter” hydrogen cloud and remnant of the universe’s early formation about 14 million light-years from Earth.
