HOW

"The Universe"

The Universe is everything we can touch, feel, sense, or detect. It is a huge wide open space that holds everything from small particles to very big ones. It includes living things, planets, stars, galaxies, light, and even time. No one knows just how big the Universe is. Before the birth of the Universe, Time, Space, and Matter did not exist. We use Time to order events in the past, present, and future. Most of the universe is just emptiness- there is nothing there at all. It is dark. That is the Space. Within the space, there is a small amount of things. The matter is everything around us. How Big is the Universe? No one knows the exact size of the Universe. The universe contains everything that exists including the Earth, Planets, Stars, Space, and Galaxies. The universe contains billions of galaxies; each contains millions or billions of stars. The space between the stars and galaxies is largely empty. The Universe is amazingly huge. It would take a modern jet fighter more than a million years to reach the nearest star to the Sun. Traveling at the speed of light ( 300,000 km per second ), it would take 100,000 years to cross our Milky Way galaxy alone. The Universe is Expanding One of the interesting things about the universe is that it is always expanding. It's growing larger and larger all the time. Not only is it growing larger, but the edge of the universe is expanding at a faster and faster rate. Scientists think that the edge of the universe is expanding faster than the speed of light No one knows the exact size of the Universe because we cannot see the edge if there is one. All we do know is that the visible Universe is at least 93 billion light years across ( A light year is the distance light travels in one year - about 9 trillion km . ) The Universe has not always been the same size. Scientists believe it began during the Big Bang. which took place nearly 14 billion years ago. Since then, the Universe has been expanding outward at a very high speed. So the area of space we now see is billions of times bigger than it was when the Universe was very young. The galaxies are also moving further apart as the space between them expands What is the Universe made of? Even though the Earth seems really big to us, it's actually a very tiny part of the universe. The Sun has a mass of 330,000 times of the Earth. The Sun is just one star in the Milky Way Galaxy that contains over 300 billion stars and scientists estimate that there are over 170 billion galaxies in the universe. However, most of the universe is what we think of as empty space. All the stars together only make up around half a percent of the universe. The majority of the universe consists of something scientists call dark matter and dark energy How Universe was formed? Scientists believe that about 13.7 billion years ago, a powerful explosion called the Big Bang happened. This powerful explosion set the universe into motion and this motion continues today. Scientists are not yet sure if the motion will stop, or change its direction. or keep going forever.