Once a star comes to the end of it's life cycle and collapses in on itself or novas(explodes)the remains form a new star,new solar system,perhaps new life.

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Star

A star is a massive, luminous ball of plasma which creates a fusion reaction(equivelent to hundreds of millions of nuclear weapons exploding at once in the one place then contained by the stars gravity).The sun that Earth revolves around is a star.

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Black hole

A region of space in which the gravitational field is so powerful that nothing, not even electromagnetic radiation (e.g. visible light), can escape its pull after having fallen past its event horizon. The term derives from the fact that the absorbsion of visible light renders the hole's interior invisible.As you get closer to a black hole time slows,so if you were to return to Earth after being near a black hole you would be in the future.

Image-Well we can't actuallly see a black hole,just the objects around it being sucked in.

Wormhole

In physics, a wormhole is a hypothetical topological feature of spacetime that is basically a shortcut(portal) through space and time. Spacetime can be viewed as a 2D surface, and when 'folded' over, a wormhole bridge can be formed eg if spacetime was a piece of paper and you wanted to get to the other side quicker you could fold the spacetime.

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Galaxy

A group of stars massed together.The Milky Way galaxy we are in has hundreds of billions of stars.A galaxy is held together by the gravity of a black hole.There is hundreds of billions of galaxies in the universe with hundreds of billions of stars like our Milky Way galaxy so imagine the possibility for life elsewhere in the universe.

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