Darkness remains in space because there is no fixed air or other gases path for the passage of light in space and for this there is not even the necessary amount of oxygen, and due to this, other planets and other planets in the light of big planets and stars. Elements receive light. Some people think that if there is no oxygen in space, then the light of the sun which is due to fire, then how is the fire going? So the answer is also that there is abundant hydrogen on the Sun, and there are more than 20 nuclear explosions there every time. And that is why the next is present on the Sun all the time. And that heat released by nuclear explosion is obtained on Earth and other planets. To go into space, a person is made an astronaut, and an astronaut has to carry all the things he needs to survive on Earth. Such as oxygen, food, water and many other things because all those things are not available in space. There is a complete vacuum in space. There is no oxygen to breathe in space, so an astronaut has to carry many oxygen cylinders with him. Along with this, some dry fruits and frozen food have to be kept with them, which does not spoil with time. And they get crackers, fruits etc. in the form of frozen food. And frozen food is mainly found in the form of dry fruits and many other food freezing processes are being started and efforts are being made to preserve different types of food for a long time. An astronaut needs a sleeping bag along with all these things where he sleeps, as there is no separate sleeping space on the capsule.