A deep look into the universe that was created by the Big Bang 13.8 billion years ago. We see light today that was sent out 13.8 billion light years ago. However, due to the continuously accelerated expansion, the radius of the universe is currently 46 billion light years. The priest and physicist Georges Lemaître showed in 1927, on the basis of Einstein's general theory of relativity, that the universe is expanding. Even Albert Einstein thought that was impossible at first; for him the universe was an immutable, finite structure. In this spherical space, however, radio telescopes have discovered the afterglow and background radiation of the Big Bang in all directions. Since the light of the very first objects was shifted into the infrared range of the spectrum by the expansion (redshift), even the largest and most powerful optical telescopes can no longer detect objects at the edges. Objects billions of light years away appear like time machines. For galaxies that are "only" millions of light years away, the review time becomes insignificant compared to their lifespan. This is how distant galaxies differ from the closer ones. They show the early stages of galactic evolution. Highly active galaxies such as quasars, but also collisions and fusions, are very common in the early stages. Almost all distant galaxies are irregular. They have a lot of dust and gas. The first very bright and large stars were born in them. At this stage the stars were mostly made up of hydrogen and helium. The heavy elements only emerged with the death of the first stars. However, 95 percent of the constituent parts of the universe are still unknown to us. The proportion of ordinary matter made up of protons, neutrons and electrons, make up 4.1 percent of the total energy density of the universe. Most of this matter is in the gas clouds of hydrogen and helium that mainly occur in and between galaxies. 23 percent of the universe is made up of dark matter. It becomes verifiable through the influence of its gravity in the rotation and movement of the galaxies. The largest share with 72 percent is dark energy and is driving expansion. The latest measurements confirm that the universe is flying apart at unbelievable speed. But we still don't know what the dark matter and the dark energy are made of.