Dark Matter Archives

July 16, 2024July 16, 2024 by Mark Thompson

Pulsars are the Ideal Probes for Dark Matter

This artist's concept shows a pulsar, which is like a lighthouse, as its light appears in regular pulses as it rotates. Pulsars are dense remnants of exploded stars, and are part of a class of objects called neutron stars. http://photojournal.jpl.nasa.gov/catalog/PIA21085 Credit NASA/JPL-Caltech

Pulsars are the remnants of the explosion of massive stars at the end of their lives. The event is known as a supernova and as they rapidly spin they sweep a high energy beam across the cosmos much like a lighthouse. The alignment of some pulsar beams mean they sweep across Earth predictably and with precise regularity. They can be, and often are used as timing gauges but a team of astronomers have found subtle timing changes in some pulsars hinting at unseen mass between pulsars and telescopes—possibly dark matter entities.

July 13, 2024July 13, 2024 by Mark Thompson

Mapping the Stars in a Dwarf Galaxy to Reveal its Dark Matter

Dark matter is curious stuff! As the name suggests, it’s dark making it notoriously difficult to study. Although it’s is invisible, it influences stars in a galaxy through gravity. Now, a team of astronomers have used the Hubble Space Telescope to chart the movements of stars within the Draco dwarf galaxy to detect the subtle gravitational pull of its surrounding dark matter halo. This 3D map required studying nearly two decades of archival data from the Draco galaxy. They found that dark matter piles up more in the centre, as predicted by cosmological models.

June 27, 2024June 29, 2024 by Laurence Tognetti

Dark Matter: Why study it? What makes it so fascinating?

Image from NASA’s Hubble Space Telescope of a galaxy cluster that could contain dark matter (blue-shaded region). (Credit: NASA, ESA, M. J. Jee and H. Ford et al. (Johns Hopkins Univ.))

Universe Today has had some incredible discussions with a wide array of scientists regarding impact craters, planetary surfaces, exoplanets, astrobiology, solar physics, comets, planetary atmospheres, planetary geophysics, cosmochemistry, meteorites, radio astronomy, extremophiles, organic chemistry, black holes, cryovolcanism, and planetary protection, and how these intriguing fields contribute to our understanding regarding our place in the cosmos.

Here, Universe Today discusses the mysterious field of dark matter with Dr. Shawn Westerdale, who is an assistant professor in the Department of Physics & Astronomy and head of the Dark Matter and Neutrino Lab at the University of California, Riverside, regarding the importance of studying dark matter, the benefits and challenges, the most exciting aspects about dark matter he’s studied throughout his career, and advice for upcoming students who wish to pursue studying dark matter. So, what is the importance of studying dark matter?

June 25, 2024June 25, 2024 by Evan Gough

Another Strike Against Primordial Black Holes as an Explanation for Dark Matter

An image based on a supercomputer simulation of the cosmological environment where primordial gas undergoes the direct collapse to a black hole. Credit: Aaron Smith/TACC/UT-Austin. — An image based on a supercomputer simulation of the cosmological environment where primordial gas undergoes the direct collapse to create black holes. Credit: Aaron Smith/TACC/UT-Austin.

The quest to understand dark matter has taken many twists and turns. It’s a scientific tale but also a human one. We know there’s a missing mass problem, but astrophysicists and cosmologists can’t figure out what the missing matter is. One of the most interesting potential solutions is primordial black holes (PBHs).

However, new research suggests that PBHs can only make up a small portion of dark matter if any at all.

June 10, 2024June 10, 2024 by Evan Gough

If Gravity Can Exist Without Mass, That Could Explain Dark Matter

Researchers are making progress mapping dark matter, but they don't know what it is. This is a 3D density map of dark matter in the local universe, with the Milky Way marked by an X. Dots are galaxies, and the arrows indicate the directions of motion derived from the reconstructed gravitational potential of dark matter. Image Credit: Hong et al., doi: 10.3847/1538-4357/abf040.

Dark Matter is Nature’s poltergeist. We can see its effects, but we can’t see it, and we don’t know what it is. It’s as if Nature is playing tricks on us, hiding most of its mass and confounding our efforts to determine what it is.

June 5, 2024June 5, 2024 by Evan Gough

Primordial Black Holes Can Only Explain a Fraction of Dark Matter

This artist's illustration shows what primordial black holes might look like. In reality, the black holes would struggle to form accretion disks, as shown. Image Credit: NASA’s Goddard Space Flight Center

What is Dark Matter? That question is prominent in discussions about the nature of the Universe. There are many proposed explanations for dark matter, both within the Standard Model and outside of it.

One proposed component of dark matter is primordial black holes, created in the early Universe without a collapsing star as a progenitor.

June 4, 2024June 4, 2024 by Evan Gough

Evidence of Dark Matter Interacting With Itself in El Gordo Merger

Image from a computer simulation of the distribution of matter in the universe. Orange regions host galaxies; blue structures are gas and dark matter. Credit: TNG Collaboration

The Standard Model of particle physics does a good job of explaining the interactions between matter’s basic building blocks. But it’s not perfect. It struggles to explain dark matter. Dark matter makes up most of the matter in the Universe, yet we don’t know what it is.

The Standard Model says that whatever dark matter is, it can’t interact with itself. New research may have turned that on its head.

May 8, 2024May 8, 2024 by Evan Gough

Roman Space Telescope Will Be Hunting For Primordial Black Holes

When astrophysicists observe the cosmos, they see different types of black holes. They range from gargantuan supermassive black holes with billions of solar masses to difficult-to-find intermediate-mass black holes (IMBHs) all the way down to smaller stellar-mass black holes.

But there may be another class of these objects: primordial black holes (PBHs) that formed in the very early Universe. If they exist, the Nancy Grace Roman Space Telescope should be able to spot them.

May 4, 2024May 4, 2024 by Brian Koberlein

The Universe Could Be Filled With Ultralight Black Holes That Can't Die

This simulated image shows how black holes bend a starry background and capture light. Credit: NASA’s Goddard Space Flight Center

It’s that time again! Time for another model that will finally solve the mystery of dark matter. Or not, but it’s worth a shot. Until we directly detect dark matter particles, or until some model conclusively removes dark matter from our astrophysical toolkit the best we can do is continue looking for solutions. This new work takes a look at that old theoretical chestnut, primordial black holes, but it has a few interesting twists.

April 16, 2024April 16, 2024 by Evan Gough

The Milky Way’s History is Written in Streams of Stars

This artist’s impression shows a myriad of stellar streams in and around the Milky Way. These stretched-out remnants of dwarf galaxies and star clusters showcase gravitational interactions between stars, clumps of dark matter, and the entire galaxy. Rubin Observatory will reveal many more stellar streams than we have seen thus far, enabling scientists to study our galaxy’s history and properties of dark matter in more detail than ever before. Image Credit: NOIRLab

The Milky Way is ancient and massive, a collection of hundreds of billions of stars, some dating back to the Universe’s early days. During its long life, it’s grown to these epic proportions through mergers with other, smaller galaxies. These mergers punctuate our galaxy’s history, and its story is written in the streams of stars left behind as evidence after a merger.

And it’s still happening today.