What is Dark Matter?

Dark matter is a type of matter that cannot be observed directly because it does not emit, absorb, or reflect light. It is different from ordinary matter, which includes atoms and molecules that make up everything we can see and touch.

Importance of Dark Matter

Dark matter plays a crucial role in the structure and formation of the universe. It is believed to be the "glue" that holds galaxies together, as without its gravitational pull, galaxies would fly apart. Its presence can be inferred from the way galaxies rotate and how they interact with each other.

Detection of Dark Matter

Scientists have been trying to detect dark matter for decades using various methods, such as direct and indirect detection experiments, as well as studying the effects of its gravitational pull on visible matter.

Composition of the Universe

It is estimated that dark matter makes up about 27% of the universe, while ordinary matter (the matter we can see and interact with) accounts for only about 5%. The rest of the universe is made up of dark energy, which is another mysterious component that drives the acceleration of the universe's expansion.

Study Guide

To understand dark matter, it is important to grasp the following key concepts:

The difference between dark matter and ordinary matter
The gravitational influence of dark matter on galaxies
Methods used to detect dark matter
The composition of the universe, including the proportions of dark matter, ordinary matter, and dark energy