Why Do We Believe Galaxy Clusters Are Rich in Dark

question 18

Essay

Why do we believe galaxy clusters are rich in dark matter?

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Definitions:

Chest Tube

A medical device inserted into the pleural space around the lungs to remove air, fluid, or pus, often used after surgery or trauma.

Petroleum Gauze

A type of medical dressing coated with petroleum jelly to prevent it from sticking to wounds, facilitating healing and pain reduction during dressing changes.

Suction Equipment

Suction equipment refers to medical devices used to remove bodily secretions and fluids from patients to clear their airways.

Hemostat

A surgical instrument used to control bleeding by clamping blood vessels or tissues.