Almost invisible galaxy challenges dark matter theories.

"The discovery of Nube, a faint and extended dwarf galaxy, challenges existing astrophysical models. Its unique characteristics might provide new insights into the universe and the nature of dark matter. (Artist’s concept.) Credit: SciTechDaily.com" (ScitechDaily, Ghost in the Cosmos: Almost Invisible Galaxy Challenges Dark Matter Model)

"“One possibility which is attractive, is that the unusual properties of Nube are showing us that the particles which make up dark matter have an extremely small mass” (ScitechDaily, Ghost in the Cosmos: Almost Invisible Galaxy Challenges Dark Matter Model)) 

Spanish astronomers made new fundamental observations of a dwarf galaxy called "Nube". That galaxy is almost invisible. And that thing makes it interesting. The new observations caused astronomers to introduce that dark matter has an extremely small mass. If hypothetical WIMPs weakly interacting massive particles are small-size particles with extremely slow spin, that thing can explain why that matter is impossible to detect. 

There is the possibility that the shape of the WIMP is so high energy that it tunnels itself even through elementary particles. In some other models, dark matter particles' energy level is so low, that it pulls energy into itself. And if energy flows only to the object, that makes it invisible. So in that case, the dark energy is the radiation that reflects from dark matter particles core. 

"The measurements of dark matter are made by observing gravitational lensing. And another way to measure the invisible is to calculate some object's mass. Then the system calculates the predicted rotation speed. And then compile it with the observations. Those observations tell if there is more material than there should be." (ScitechDaily, Ghost in the Cosmos: Almost Invisible Galaxy Challenges Dark Matter Model)

"The Nube galaxy. The figure is a composition of a colour image and a black and white image, to pick out the background. Credit: GTC/Mireia Montes" (ScitechDaily, Ghost in the Cosmos: Almost Invisible Galaxy Challenges Dark Matter Model)

So WIMP is a lightweight particle that looks like quarks or leptons. But it's smaller than them. The forms of dark matter are a mystery. And in some visions the dark matter particle WIMPs could be particles that orbit electrons. New observations about galaxies and black holes challenging traditional cosmological models. 

The interaction between dark matter and visible material is purely gravitational. But if the relation between WIMP's size and electron is the same as electron and proton. That could explain, why the only known interaction between dark matter and visible matter is gravitational. 

There are galaxies with dark matter and galaxies with no dark matter. That thing tells us that dark matter is not distributed evenly. This means that dark matter can form structures similar to cosmic nebulas. Or it's possible.  That dark matter can form planets, that are invisible to us. 

Dark matter is a fascinating thing. The invisible matter. But can interact through gravity. There is a theory that energy level determines what its name is. So the lepton's energy level determines if it's an electron or muon. The same way the energy level determines is particle down or top quark. That means that it's possible. That energy level determines whether can we see particles or not. 

https://scitechdaily.com/ghost-in-the-cosmos-almost-invisible-galaxy-challenges-dark-matter-model/

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