Question

Astronauts in space do talk to each other

Answer 1

Communicate with via UHF radio

Answer 2

Space is a big vaccum where there is no air in astronaut suit oxygen is pumped in which enables them to speak there is a microphone in that suit along with earphones these are connected to a spaceship when one speaks the waves reach the spaceship via vhf radio waves and is transported from the ship also via this this is the way through which astronauts speak to each other