The great space.

Imagine endless space. A distance of miles that would take tens of pages to write it down. Now Imagine that at the centre of this space there is a big explosion and in the first second of this explosion hydrogen, helium and other light elements are starting to create , it starts to cool down and all these gases are starting to get close to each other. They slowly start to form a solid stones , stones form a rocks , rocks start to form a giant rock so big and massive that it’s core is getting hotter and hotter and it gets so warm that hydrogen on the surface of the planet is changing into helium and trough that process light and warmth is creating. You just saw a creation of a star.

The smallest star ever.

Now , what if the star would be a size of a needle top ? What if that star would be 10,000 times our sun weight? Well , that would be the most dangerous force in the universe.A force so powerful that it would “eat” everything , even light. Yes , there are things like this in our world, they’re called black holes. A black hole is actually a star , but very old star. Star when it’s reaching end of it’s hydrogen supplies , it starts to “die”, that means star is enlarging to very big volume and then it explodes. But sometimes , not often, but sometimes star instead of exploding , it falls down inside of it’s own core , like an old building. In that process star is smashing down itself into very small size , but it keeps it’s weight. That’s how black hole is created. Gravitation of black hole is so big , that objects closing to it are changed in to a “spaghetti” and it starts to circle the black hole with speed of light until it crashes into the hole. So even light can’t resist it’s force. That’s why it’s BLACK hole , not white hole or something.

Dark matter and dark energy.

Scientists have calculated the amount of matter and energy in the universe , and they have discovered that something is missing. Well , according to these calculations , everything we can see , that means gases , stars and other things floating in the universe are only 4 % of the whole matter and energy in the universe. so they connected few unexplained things and created phrases like dark matter (23 %) and dark energy (73 %). Dark matter is connection of unexplained gravitation that was effecting the stars and other objects and missing energy of the universe. And dark energy is connection of problem of space expanding and missing energy of the universe. Universeis expanding , because of the big bang , but it’s speed is growing , that is the problem that dark energy explains. Dark energy is according to scientists force that makes the expansion faster.

Space , is it infinite?

Well according to last known info, universe is 13.73 (± 0.12) and diameter of observable universe is 93 billion light years (light year - a distance that light travels for one year).

It may seem impossible that two galaxies on opposite sides can be separated by 93 billion light years after only 13 billion years, since special relativity states that matter cannot be accelerated to exceed the speed of light in a localized region of space-time. However, according to general relativity, space can expand with no intrinsic limit on its rate; thus, two galaxies can separate more quickly than the speed of light if the space between them grows. It is uncertain whether the size of the Universe is finite or infinite.