What is in space

Theoretically, the space starts about 100 kilometers above the surface of the planet, where there is no air to breathe or to dispel the light. In this zone, blue gives way to black because the oxygen molecules are not abundant enough to make the blue sky as in our skies. The space is also an empty area through which the sound can not move because the molecules are unable to transmit the sound wave between them because of the great distances that separate these particles. Although the human space may seem empty, on the contrary, research has shown that there are forms of radiation emitted by the universe, gases, dust and other elements floating in the vast universe, as well as stars, planets and galaxies in the most frequented regions. Nobody knows exactly the size of the universe because it is developing so far, in addition to the weakness of our techniques compared to the size of the universe and its vast distances, for example , the light cuts in less than a year about 5.8 trillion kilometers, which can only be achieved by existing technologies on Earth.

What is in space

• Galaxy galaxies

The galaxy of the Milky Way (our galaxy) is only one of the billions of galaxies in the universe. Scientists estimated that there were at least 100 billion galaxies in the visible universe, each filled with stars.

The star is a ball of light gas that we find in space, mainly hydrogen and helium, held together by its own appeal. The nuclear fusion reactions inside it strengthen the star against the attraction of others and produce photons and heat, as well as small amounts of heavier elements. The sun is the star closest to the earth

The number of planets exceeds the number of stars in our galaxy. Only eight are known, including our planet. Can be divided into:

• Rocky: He is closest to the sun Mercury, Venus, Earth and Mars.
• Invasive Giant: Jupiter and Saturn.
• Ice Giants: Uranus and Neptune.
• Behind Neptune we find Pluto, who recently joined the category of dwarf planets.

• asteroids

They are also called small planets. Is a rocky remnant without air from the space formed with the formation of our solar system about 4.6 billion years ago. The number of asteroids currently known is estimated at 795,071 asteroids. Most of these ancient space debris orbiting the sun lie between Mars and Jupiter in the main asteroid belt. Are of different sizes, ranging from 329 miles (530 km) to objects less than 33 feet (10 meters) wide. The mbad of all the asteroids in our combined solar system is less than the mbad of the Earth.

Comets are cosmic ice balls formed from gas, dust and frozen rocks orbiting the sun. Comets can reach large sizes such as the size of a city or a city. As the comet approaches the sun's orbit, its temperature rises, spreading gases and dust, forming a huge giant head that extends far away from the sun, over a distance of several million kilometers. There are millions of comets orbiting the Sun, but the only known number of them is 3573.

• Black holes

The black hole is a place in the space of high gravity (almost infinite) pulling everything that goes by its sides so that light can not escape so people can not see it. The density and its infinite appeal are explained by the fact that a large material (dead star, for example) is compressed in a very small space. Scientists, big and small, think that smaller holes can be the size of an atom but the mbad of a mountain, others can be millions of times the size of the sun.

• Dark matter and energy

Recently, it was discovered that nearly 68% of space was dark energy, 27% dark matter and only 5% of our universe. What we know about this article is far less than we know it. It's still a secret that has baffled scientists so far.

Despite all the efforts, research, books, satellites and space stations, much remains to be learned about our universe, its structure, its beginnings and its end. Maybe we do not know what we know 5%, and the rest is still unknown to us.