Dark matter is exceptionally fascinating. Unfortunately for us, it is also invisible, so it was a real challenge for scientists to study it.
Though dark matter makes up 85% of all matter in the Universe, it does not interact with light, which means that it can only be observed with the help of the gravitational influence it has on light and other matter.
To complicate things even more, efforts to detect dark matter directly on our planet haven’t returned positive results.
What Do We Know About It?
Though it is such an oddity, scientists managed to learn some details about it.
Dark matter is cold. It clumps together, forming the seeds of galaxy clusters.
It often produces halos around galaxies, thus being responsible for the most of a galaxy’s mass.
Unfortunately, there are many unanswered questions about dak matter that scientists are trying to answer. Their pursuit of answers developed new models for dark matter, comparing them to observation to test their accuracy.
One way to analyze a model’s behavior is by simulating it.
A team from the Harvard& Smithsonian Center for Astrophysics ran an advanced simulation of the dark matter cosmos, and the findings were impressive.
The precision of all simulations heavily depends on the assumptions the creator makes about dark matter.
In the current case, the team hypothesized that dark matter consists of weakly interacting massive particles (WIMPs), with masses about 100 times that of a proton.
WIMPs are some of the most popular dark matter theories.
Similar computer models of WIMP dark matter were conducted before.
However, the new one is extraordinarily high in resolution, simulating characteristics on a scale spanning across thirty orders of magnitude.
In that simulation, dark matter formed halos around galaxies.
Curiously, it was revealed that halos also formed at all mass scales, from little, planet-mass halos, to galactic halos, to massive halos that are typically found nearby galaxies clusters.
Those halos have a comparable structure, where they are denser toward the center, becoming more diffuse at their edges.
Dark matter has a particular trait – that phenomenon happens at all scales.
Small scale halos are tough to detect through their gravitational impact on light, but they could be vital in revealing how dark matter affects itself.
A hypothesis about dark matter is that when dark matter particles collide, gamma rays are emitted.
Some gamma-ray detections have suggested a gamma-ray excess originating in the center of our galaxy, which could be provoked by dark matter.
In that specific model, most gamma rays are provoked by dark matter produced by smaller halos.
Halo Size VS. Energy
The scale of a halo affects the energy spectrum of gamma rays, so the model makes particular predictions about gamma-ray excesses that should be present in our galaxy and others alike.
Dark matter still is one of the biggest mysteries of modern astronomy.
Though the goal is to detect it directly, until that becomes doable, simulations like the previously mentioned one are our best bet to understand the dark matter better.
We hope that scientists find the key to solving the dark matter mystery as soon as possible.
Who knows what secrets it hides? Could it be the first step in understanding more about the Universe? That remains to be seen!