How do astronomers know that dark matter is "cold"?
A) laboratory measurements of its properties
B) computer simulations of structure formation
C) measurements of its annihilation radiation
D) gravitational lensing

Question

Quizplus · Accepted Answer

Astronomers know that dark matter is "cold" because computer simulations of structure formation suggest that the CDM (cold dark matter) model is the most accurate description of our universe. This model assumes that dark matter particles move slowly, or "coldly," which allows them to clump together and form structures like galaxies. Additionally, alternative models that assume "warm" or "hot" dark matter have been ruled out by observational evidence.

How Do Astronomers Know That Dark Matter Is "Cold