Dark matter: The phenomenon that can not be observed.
The infinities of the universe encompass many mysteries to be discovered, some that have been discovered and others that we probably overlook even when it is under our noses, in the case of dark matter, an entity full of mysteries and something that contains the largest mass of the universe , Here I will tell you a little about what is dark matter:
Our universe is composed of both energy and matter, seeing and touching matter is something we do every day, like, for example, I play the keyboard at the time of doing this post, but it happens the opposite with dark matter, because Is hypothetically a matter that can not be seen, since it is in the deepest of the space and is maintained in low temperatures, that is to say, it is very cold.
Unlike the moon that emits radiation and therefore can be observed with the naked eye through our vision, while others with the naked eye we can not easily observe because they are billions of kilometers away to the Earth.
In the case of dark matter does not emit any radiation, or in the case that the emit is not enough for it to affect the radiation detectors, resulting in that matter is impossible to see.
Not having any knowledge since it is impossible to analyze, we do not know what is formed, it is speculated that contains neutrinos, clouds of gas that do not emit light or dwarf stars.
A doubt arises, in case we can not see or touch it, ** how do we know of its existence? **
Despite being a hypothesis, over the years many evidences have emerged that demonstrate the existence of this mysterious matter.
In 1993 F.Zwicky proposed the existence of this matter as a phenomenon that can not be explained, because the speed with which the galaxies move did not agree with the movement that was expected of them.
Our universe is so vast that it will take us too many years and even millennia to discover only a small part of what it offers us, but this does nothing more than encourage those people who are passionate about this type of subject, always looking for the answers To the great unknowns that lies before us.
This post is not super clear (from the English standpoint). I have a few remark / comment.
We know neutrinos exist and we have observed them. And they are not dark matter.
Also, connecting dark matter to the galaxy rotation curves is a bit a reduction. There are today many indirect evidence for it. You can for instance check some of my posts of the last month on this topic.
And finally, there may just be no dark matter and modified gravity instead :)
It's cool find a teacher of physics here, I'm studying physics and mathematics in Uni. hope some day dedicate to investigacion in areas of aplied physics :) ... And improve my level of english too haha.
Applied physics is a very important field for the future. I wish you good luck with your studies! And don't hesitate to ask me anything if needed :)
Dark matter is purely theoretical though. It could just as well end up being non-existent, and be a calculation error on humanity's part because we forgot to take yet-unknown-variables into account.