Universe is infinite, it’s secrets are very unknown,

Universe is a vaccum , where you can’t listen sound, because to travel sound needs a medium, which in vacuum it is not there

In space, there are planets, stars , asteroids, galaxies, black holes , between two planets, there are dust particles

In universe, there is dangerous radiation, which has infrared ray , gamma ray, cosmic rays

In universe there is darkness all around, no air , no oxygen, because of sun there is light but on some planets

How big is universe, no one could tell , it is infinite

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