Our universe is full of stars and galaxies and its size is bigger than imagined. We live in the Milky Way galaxy. It is one of the many galaxies in the universe. However, most galaxies in the universe are moving away from us and simultaneously expanding. Many galaxies have already passed beyond our reach.
The universe is expanding and as a result, the distance between objects is increasing. This means the galaxies are moving away from each other. Even objects that were once close to each other are now spaced apart due to the expansion of space.
The universe is so vast that we will never see it all. There are galaxies that are beyond our reach, even though we can see them. This is because the expansion of space is pushing them away faster than the speed of light. Looking back in time, scientists have been able to create a 3D picture of the cosmic star formation potential.
As the universe expands, the density of matter thins, and the radiation cools. There are trillions of trillions of galaxies in the observable universe, but we can only observe a tiny fraction of them.
The expansion of the universe is known as the Hubble constant. Scientists have found that the rate of expansion of the universe is slowing down day by day. Again, a study after 1990 showed that this speed is increasing due to dark energy and the universe will continue to expand.
Scientists may never reach all the galaxies beyond a certain distance. Even running at the speed of light would not be possible. Scientists can only reach galaxies within 18 billion light years.