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Astronomers Spot Distant Galaxies Lacking Dark Matter
· Confirmed
In Short: Astronomers have discovered 19 more galaxies that seem to lack dark matter, according to a study published November 26 in Nature Astronomy.
Astronomers have discovered 19 more galaxies that seem to lack dark matter, according to a study published November 26 in Nature Astronomy. The new findings, led by Qi Guo of the Chinese Academy of Sciences, add to the growing body of evidence challenging the standard model of galaxy formation.
The latest batch of galaxies missing dark matter was discovered when Guo and her team explored the nature of 324 dwarf galaxies using data from the Arecibo Observatory in Puerto Rico and the Sloan Digital Sky Survey.
In 2018, researchers led by Pieter van Dokkum of Yale University found a bizarre, ghostly galaxy named NGC 1052-DF2 that seemed to contain very little, if any, dark matter. This discovery was the first of its kind and sparked significant debate in the scientific community.
According to the study, these galaxies could form in a particular way that requires much less dark matter than previously thought. This challenges the standard ideas of how galaxies form and suggests that dark matter might not be as integral to galaxy formation as previously believed.
The findings are particularly intriguing because dark matter is thought to make up 27% of the total mass/energy content of the universe, according to astronomers. The invisible substance is crucial for understanding the structure and evolution of galaxies.
Guo's team's results suggest that a population of dwarf galaxies could form in a way that requires much less dark matter than those in the Local Group and those found in simulations. This challenges the standard model of galaxy formation and encourages scientists to revisit the nature of dark matter.
The discovery of these galaxies without dark matter is unexpected and challenges the standard ideas of how galaxies work. It shows that dark matter has its own separate existence apart from other components of galaxies.
They are star-deficient but seem to contain, at most, 400 times less dark matter than expected.
The findings have implications for our understanding of dark matter and its role in galaxy formation. They suggest that dark matter may interact with other dark matter in ways other than through the force of gravity, as observed in the merging cluster El Gordo.
Astronomers have long used gravitational lensing to track dark matter, the invisible substance thought to make up 85 percent of all matter in the universe. This technique involves observing how the gravity of a massive object bends light from a more distant source.
The new findings are very hard to explain using the standard galaxy formation model, according to lead author Qi Guo. This result is unexpected and encourages people to revisit the nature of dark matter.
The discovery of these galaxies without dark matter is significant because it challenges the standard ideas of how galaxies work and shows that dark matter has its own separate existence apart from other components of galaxies.
What's confirmed
- Astronomers have discovered 19 more galaxies that seem to lack dark matter, according to a study published November 26 in Nature Astronomy. The new findings, led by Qi Guo of the Chinese Academy of Sciences, add to the growing body of evidence challenging the standard model of galaxy formation.
- The latest batch of galaxies missing dark matter was discovered when Guo and her team explored the nature of 324 dwarf galaxies using data from the Arecibo Observatory in Puerto Rico and the Sloan Digital Sky Survey.
- In 2018, researchers led by Pieter van Dokkum of Yale University found a bizarre, ghostly galaxy named NGC 1052-DF2 that seemed to contain very little, if any, dark matter. This discovery was the first of its kind and sparked significant debate in the scientific community.
- According to the study, these galaxies could form in a particular way that requires much less dark matter than previously thought. This challenges the standard ideas of how galaxies form and suggests that dark matter might not be as integral to galaxy formation as previously believed.
- The findings are particularly intriguing because dark matter is thought to make up 27% of the total mass/energy content of the universe, according to astronomers. The invisible substance is crucial for understanding the structure and evolution of galaxies.
- Guo's team's results suggest that a population of dwarf galaxies could form in a way that requires much less dark matter than those in the Local Group and those found in simulations. This challenges the standard model of galaxy formation and encourages scientists to revisit the nature of dark matter.
- The discovery of these galaxies without dark matter is unexpected and challenges the standard ideas of how galaxies work. It shows that dark matter has its own separate existence apart from other components of galaxies.
- They are star-deficient but seem to contain, at most, 400 times less dark matter than expected.
- The findings have implications for our understanding of dark matter and its role in galaxy formation. They suggest that dark matter may interact with other dark matter in ways other than through the force of gravity, as observed in the merging cluster El Gordo.
- Astronomers have long used gravitational lensing to track dark matter, the invisible substance thought to make up 85 percent of all matter in the universe. This technique involves observing how the gravity of a massive object bends light from a more distant source.
- The new findings are very hard to explain using the standard galaxy formation model, according to lead author Qi Guo. This result is unexpected and encourages people to revisit the nature of dark matter.
- The discovery of these galaxies without dark matter is significant because it challenges the standard ideas of how galaxies work and shows that dark matter has its own separate existence apart from other components of galaxies.
What's still developing
- “Something that caught my attention very early on was the fact that the galaxy [DF2] was not only anomalous for not having dark matter, but also for having an extraordinarily bright population of globular clusters,” Trujillo told Astronomy.
- Close-in Mercury moves much quicker than distant Neptune.
- It meant the Andromeda galaxy must be saturated with huge amounts of invisible matter, stretching far from the galaxy’s center.
- Dating back to the very early stages of cosmic history and caused by normal matter getting “bounced” away from a clustering center, it leaves an imprint that looks a bit like a cosmic bubble: where galaxies are more likely to be found a specific distance away from another rather than slightly closer or farther away.
- “They have this ghostly appearance,” said Michael Keim, an astrophysicist at Yale University.
- In a new study, astronomers used data from the NASA/ESA Hubble Space Telescope to calculate a more accurate distance to an ultra-diffuse galaxy called NGC 1052-DF2 (DF2 for short).
- Massey added: “We are finally homing in on dark matter from above and below — squeezing our knowledge from two directions.” [1] Astronomers have found that the total mass/energy content of the Universe is split in the proportions of 68% dark energy, 27% dark matter, and 5% “normal” matter.
- Using data from NASA’s James Webb Space Telescope and Chandra X-ray Observatory, a team of astronomers discovered this low-mass supermassive black hole just 1.5 billion years after the big bang.
- The black hole is pulling in matter at a phenomenal rate — over 40 times the theoretical limit.
- Black holes (center) typically grow by consuming matter via pancake-like accretion disks.
- A few years ago, while using NASA’s James Webb Space Telescope (JWST) to survey some of the Universe’s earliest galaxies, astronomers noticed a peculiar and extremely bright “Little Red Dot” they’ve since concluded is a mashup of a black hole and a star.
- But studying these bright regions, called active galactic nuclei (AGNs), that are sprinkled across the cosmos can teach astronomers about how stars and galaxies form—and possibly shed light on our Milky Way.