Image of SpaceX's Falcon orbital rocket liquid oxygen tank

Some black objects that are visible in the tank are compressed helium capsules that are stored in cryogenic (super cold) liquid oxygen in order to reduce their density and make them more compact.
Liquid oxygen is the common oxidizer of liquid fuel rockets and by combining with the rocket's main fuel, it causes ignition and propulsion.

#Tank
#Fuel
#Rocket
#Aerospace