dark matter tagged posts

Astronomers Solve Dark Matter Puzzle of Strange Galaxy

Image and amplification (in colour) of the ultra-diffuse galaxy Dragonfly 44 taken with the Hubble space telescope. Many of the dots on the galaxy are the globular clusters studied in this article to explore the distribution of dark matter. The galaxy is so diffuse that other galaxies can be seen behind it. Credit: Teymoor Saifollahi and NASA/HST.
Image and amplification (in colour) of the ultra-diffuse galaxy Dragonfly 44 taken with the Hubble space telescope. Credit: Teymoor Saifollahi and NASA/HST.

Astronomers have found that the total number of globular clusters around Dragonfly 44 and, therefore, the dark matter content, is much less than earlier findings had suggested, which shows that this galaxy is neither unique nor anomalous.

At present, the formation of galaxies is difficult to understand without the presence of a ubiquitous, but mysterious component, termed dark matter. Astronomers have measure how much dark matter there is around galaxies, and have found that it varies between 10 and 300 times the quantity of visible matter...

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Scientists Precisely Measure Total Amount of Matter in the Universe

The team determined that matter makes up about 31% of the total amount of matter and energy in the universe. Cosmologists believe about 20% of the total matter is made of regular — or “baryonic” matter — which includes stars, galaxies, atoms, and life, while about 80% is made of dark matter, whose mysterious nature is not yet known but may consist of some as-yet-undiscovered subatomic particle. (UCR/Mohamed Abdullah)

A top goal in cosmology is to precisely measure the total amount of matter in the universe, a daunting exercise for even the most mathematically proficient. A team led by scientists at the University of California, Riverside, has now done just that

Reporting in the Astrophysical Journal, the team determined that matter makes up 31% of the total amount of matter ...

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Scientists shed light on Mystery of Dark Matter

Scientists know dark matter exists because of its interaction via gravity with visible matter like stars and planets.

Scientists have identified a sub-atomic particle that could have formed the ‘dark matter’ in the Universe during the Big Bang. Nuclear physicists are putting forward a new candidate for dark matter – a particle they recently discovered called the d-star hexaquark.

Up to 80% of the Universe could be dark matter, but despite many decades of study, its physical origin has remained an enigma. While it cannot be seen directly, scientists know it exists because of its interaction via gravity with visible matter like stars and planets. Dark matter is composed of particles that do not absorb, reflect or emit light.

Now, nuclear physicists at the University of York are p...

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Taking the Temperature of Dark Matter

Astronomical image
This image from the Hubble Space Telescope shows lensing of distant galaxies by gravity. UC Davis astronomers are using this phenomenon to learn more about the properties of dark matter.

Warm, cold, just right? Physicists at the University of California, Davis are taking the temperature of dark matter, the mysterious substance that makes up about a quarter of our universe.

We have very little idea of what dark matter is and physicists have yet to detect a dark matter particle. But we do know that the gravity of clumps of dark matter can distort light from distant objects. Chris Fassnacht, a physics professor at UC Davis and colleagues are using this distortion, called gravitational lensing, to learn more about the properties of dark matter.

The standard model for dark matter is ...

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