what is dark matter?

Question

what is dark matter

Answer 1

No one knows for sure what dark matter is.

The most prevalent view is that it is a kind of subatomic particle that doesn't interact with electromagnetic energy (Weakly Interacting Massive Particles - WIMPs). The best evidence is that it's some kind of a new, non-baryonic particle

An alternative is that it's normal matter like rogue planets, black holes, neutron stars, etc. These wouldn't be easily seen from earth (the black holes and neutron stars in this case wouldn't have accretion disks). These are called MAssive Compact Halo Objects (MACHOs).

All that we know for sure is that there is something that makes up to about 22% of the energy density of the universe (normal matter makes up about 4% and dark energy makes up about 74% (and before you ask, no one has a clue to what dark energy is, only what it does)) We know that dark matter exists because how galaxies rotate. To rotate as they do, a halo of matter is needed and the matter we can see isn't enough to account for it. Other observations reduced the likelihood that it was normal matter and that it was something completely new

MistWing SilverTail

Answer 2

No opne knows just yet but it accounts for 21% of the energy in the Universe. Dark energy accounts for another 75% - and again we dont know what that is either. So believe it or not there is only 4% of the universe which we know something about and 96% for which we know next to nothing about.

Answer 3

In physics, a black body is an object that absorbs all electromagnetic radiation that falls onto it. No radiation passes through it and none is reflected, yet in classical physics, it can theoretically radiate any possible wavelength of energy. Despite the name, black bodies are not actually black as they radiate energy as well. The amount and type of electromagnetic radiation they emit is directly related to their temperature. Black bodies below around 700 K (430 °C) produce very little radiation at visible wavelengths and appear black (hence the name). Black bodies above this temperature, however, begin to produce radiation at visible wavelengths starting at red, going through orange, yellow, and white before ending up at blue as the temperature increases.

Answer 4

Soot

Answer 5

Dust!

Answer 6

what is the space between atoms??

Answer 7

ECLIPSE OF THE SUN.