Question

why do astronauts carry gas cylinders containing oxygeneted air??

Answer 1

the astronaut carry a gas cylinder (o2) because of no avability of o2in the ( no atmosphere ) so its simple to breathe in they need o2

Answer 2

they carry cylinders containing oxygenated air because in space there is no o2 at all .but o2 is essential for sustaining life as we all know.