Why is it important to know the size of the universe?

There is currently no agreement on the size or shape of the universe, so astrophysicists can only make educated guesses.

Some believe that the universe is shaped like a pancake, while others believe it is spherical, like a soccer ball.

They find that "seeing" the farthest galaxies to be problematic because, given the known age of the universe, which is approximately 13.7 billion years, we should only be able to see objects that are 13.7 billion light years away. As of right now, they have identified galaxies that are roughly 45 billion light years away.

While scientists are aware that the universe is expanding at an ever-increasing rate, they are unsure of the precise rate at which this expansion is occurring. They theorize that, in the first few seconds following the big bang, the universe expanded to half its current size and has continued to do so ever since. This implies that galaxies that are 45 billion light years away from us are accelerating their motion away from us.

Scientists suggest that there may be, and probably are, galaxies farther out than 45 billion light years that we have not been able to detect yet for whatever reason. They also refer to those outer reaches as being part of the "visible universe."

Our understanding of the universe is far from complete, so we shouldn't worry about its size.

Knowledge of the universe's size is crucial for scientific research, technological development, and philosophical questions regarding the nature of reality. It also helps us understand cosmic phenomena like the universe's expansion and the formation of galaxies, stars, and planets. Knowledge of the universe's size also helps us understand the scale of existence, including our place within it, the vastness of space, and the diversity of celestial objects.