The Mystery of the "Big Bang"
What Powerful Forces Created Our Universe?
by Sara Diaz, age 13
We all have a sense of wonder. It’s part of what makes us humans. For many of us this sense of wonder leads to questions about how, when, and why the universe began. One explanation to this mystery is the Big Bang theory.
According to this theory, a small, hot ball was floating in space, when all of a sudden there was a large explosion. In fact, this was the largest explosion of all time. Scientists call it, “the Big Bang.”
According to this theory the Big Bang created, in a split second, all the forces and matter in the universe. During the explosion, particles and material flew everywhere, at all different speeds. About three hundred million years later, the stars and galaxies finally formed from hydrogen and helium gas clumps.
Because there is no evidence from this period, we can only guess as to what existed before the Big Bang. Some scientists believe there was an ocean of energy existing beyond space and time, holding within it many universes that each had the potential to burst into life. Our universe was one of the successful ones, but others may exist as well.
When the universe began, it had the same amount of energy and matter it has today. Although scientists do not know for sure what the early universe was like, they use mathematical calculations and physics applications to get an idea. Huge machines called colliders, and particle accelerators, simulate the early universe and attempt to show what happened during the Big Bang. These machines use magnets to move large amounts of particles, which bounce all over and eventually crash into each other. Some experts believe the universe could have been created this way.
By watching how fast galaxies move, we can see how the universe has expanded and determine how long it took for everything to move to where it is now. Most calculations show that the universe began about 13-15 billion years ago, but some stars seem to have been around for 18 billion years.
This is one of the many mysteries of space.
The universe may or may not keep expanding, depending on the amount of matter it carries. If there is more matter than necessary , the universe will contract or cease growing. If there is just the right amount of matter, it will stop growing. But if there’s not enough matter, it will expand forever. Scientists call this state the “Open Universe.”
Although some people take the existence our universe for granted, it is actually a constantly changing entity. It is also a place of endless mystery and many fascinating questions.
[Sources: The Big Book of Knowledge; Atlas of the Universe]