Dark Matter Archives

December 14, 2023December 14, 2023 by Mark Thompson

Dark Matter Could Cause Jupiter’s Night Side to Glow

One of the aspects of our study of the universe that fascinates me is the hunt for dark matter. That elusive material that doesn’t interact with much makes it difficult but not impossible to detect. Gravitational lenses are one such phenomena that point to its existence indeed it allows us to estimate how much there is in galaxy clusters. A paper now suggests that observations of Jupiter by Cassini in 2000 suggest we may be able to detect it using planets too.

December 4, 2023December 4, 2023 by Mark Thompson

Will Wide Binaries Be the End of MOND?

Artist view of an orbiting binary star. Credit: ESO/L. Calçada

It’s a fact that many of us have churned out during public engagement events; that at least 50% of all stars are part of binary star systems. Some of them are simply stunning to look at, others present headaches with complex orbits in multiple star systems. Now it seems wide binary stars are starting to shake the foundations of physics as they question the very theory of gravity.

November 23, 2023November 23, 2023 by Evan Gough

There Aren’t Many Galaxies Like The Milky Way Nearby. Now We Know Why

Antennas of the Very Large Array against the Milky Way. Credit: NRAO/AUI/NSF/Jeff Hellerman

The Milky Way is a barred spiral galaxy, maybe even a grand design spiral galaxy. We can’t be sure from our vantage point. But one thing is certain: there aren’t many disk galaxies like it in our part of the Universe called the supergalactic plane.

November 21, 2023November 21, 2023 by Brian Koberlein

CERN Has Joined the Search for Dark Photons

Illustration of two types of long-lived particles decaying into a pair of muons. Credit: CMS/CERN

In the search for dark matter particles, there are two main approaches. The first is to look for particles that happen to decay naturally as they pass by. This typically involves neutrino observatories such as IceCube where a dark matter particle particle colliding with a nuclei might trigger a faint burst of light. So far this has turned up nothing. The second approach is to slam particles together in a particle accelerator. This approach has also failed to find dark matter particles, but there have been enough interesting hints that CERN is having a go. Their latest run is looking for what are known as dark photons.

November 2, 2023November 2, 2023 by Brian Koberlein

A Dwarf Galaxy That's Almost All Dark Matter

A simulation of dark matter clusters around the Milky Way. Credit: J. Tumlinson (STScI)

Dark matter is a powerful cosmological model, but it isn’t without its problems. In addition to our inability to detect dark matter particles, one issue deals with the number of dwarf galaxies surrounding the Milky Way. According to the most popular models of dark matter, galaxies should be surrounded by clumps of dark matter within their dark matter halo. Since regular matter tends to gather around dark matter, that means the Milky Way should be surrounded by dwarf galaxies. While there are several known dwarf galaxies near the Milky Way, there are fewer than predicted by dark matter simulations. But perhaps there are many more dwarf galaxies we just haven’t noticed because they are made mostly of dark matter.

October 13, 2023October 13, 2023 by Brian Koberlein

Are Pulsars the Key to Finding Dark Matter?

A composite image of the Crab Nebula. Credit: X-ray: NASA/CXC/SAO; Optical: NASA/STScI; Infrared: NASA-JPL-Caltech

Ah, dark matter particles, what could you be? The answer still eludes us, and astronomers keep trying new ideas to find them. Such as a new paper in Physical Review Letters that suggests if dark matter is made of axions we might see their remnant glow near pulsars.

September 29, 2023September 29, 2023 by Brian Koberlein

Dark Matter Could Be Annihilating Inside White Dwarfs

The white dwarf Sirius B compared to Earth. Credit: ESA and NASA

As the search for dark matter particles continues to yield nothing, astronomers continue to look at ways these elusive particles might be found. One general method is to look for evidence of dark matter particle decay. Although dark matter doesn’t interact strongly with regular matter, some dark matter models predict that dark matter particles can interact with each other, causing them to decay into regular particles. There have been several searches for this effect, but there’s no clear evidence yet. But a new study suggests looking at white dwarfs could be a good approach.

September 20, 2023September 20, 2023 by Brian Koberlein

Dark Photons Could Be the Key to Both Dark Matter and the Muon Anomaly.

An artistic view of light becoming matter. Credit: Gerd Altmann, via Pixabay

If dark matter exists, then where are the particles?

This single question threatens to topple the standard cosmological model, known as the LCDM model. The CDM stands for cold dark matter, and according to the model makes up nearly 85% of matter in the universe. It should be everywhere, and all around us, and yet every single search for dark matter particles has come up empty. If dark matter particles are real, we know what they are not. We don’t know what they are.

September 13, 2023September 13, 2023 by Carolyn Collins Petersen

Quasars Have Always Had Dark Matter Halos

Illustration of an active quasar. What role does its dark matter halo play in activating the quasar? Credit: ESO/M. Kornmesser — Illustration of an active quasar. New research shows that SMBHs eat rapidly enough to trigger them. Credit: ESO/M. Kornmesser

When you look at most galaxies in the Universe, you’re looking at the homes of supermassive black holes. It now appears that quasars, which are active galaxies spitting out huge amounts of radiation from the region around their black holes, also have massive dark matter halos. It turns out they’ve always had them. And, their black hole activity has a direct connection with those halos.

September 12, 2023September 13, 2023 by Carolyn Collins Petersen

Astronomers Observe Blobs of Dark Matter Down to a Scale of 30,000 Light-Years Across

Dark matter fluctuations in the lens system MG J0414+0534. The whitish blue color represents the gravitationally lensed images observed by ALMA. The calculated distribution of dark matter is shown in orange; brighter regions indicate higher concentrations of dark matter and dark orange regions indicate lower concentrations. (Credit: ALMA (ESO/NAOJ/NRAO), K. T. Inoue et al.?

Dark matter remains mysterious and… well… dark. While we don’t yet have a definite idea of what this cosmic “stuff” is made of, astronomers are learning more about its distribution throughout the Universe. Since we can’t see it directly, observers need to use indirect methods to detect it. One way is through gravitational lensing. Another is by looking for emissions from hydrogen gas associated with small-scale dark matter structures in the Universe.