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The universe raises many questions that do not seem to have answers. The world's scientists continue to investigate in order to find clues to help solving fundamental questions that would challange paradigms.
The universe and its components
The substance of amalgam stars, planets, galaxies, solar systems ... What was it made of? In which order? Reportedly, the man knows only about 1% of the universe, that is, the most visible part. The energies that make up the cosmos are still unknown or little is known of them, especially of the so-called "dark energy" .Today no research gives an accurate explanation.
The origin of the Galaxy
Scholars place the birth of our galaxy over 4,500 million years ago, without reaching an agreement on how it was formed. After the Big Bang, the universe began to expand and cool. 400,000 years ago, protons and electrons had cooled enough to form neutral hydrogen atoms and photons, particles of light, which began to travel freely. The universe became transparent. But hundreds of millions years later, again something plucked electrons of atoms and most of the matter in the universe became ionized plasma, that remains up to today. What was due? The telescopes are able to see the universe in its infancy, when it was 400,000 years old. But among such transparency, there was a dark period, when the ionization was inaccessible. It was in that dark era when the first stars and galaxies originated.
Is there life beyond Earth?
One of the big questions of manhood is to know if intelligent life forms exist on other worlds. The myths and fantasies about the topic were born long ago, but from a scientific point of view there is not yet sufficient evidence to categorically answer the question. In our galaxy there are millions of stars, and it is hard to believe that humans are alone in this cosmic sea. A recent discovery of a group of astronomers is the presence of molecules, set from stars to more than 250 million light years, so the odds of life outside our planet increases.
The birth of rocky planets
A belief that has not yet found a full scientific confirmation is related to the formation of rocky planets, which seem to be created through various collisions and unity of particles around stars, also called cosmic dust. The available research suggests, that the powder found in the outer regions of the "brown dwarf", is an object like a star, but smaller, that could be part of the origin of the planets.
The sun king
That star that illuminates the earth and gives heat holds many mysteries. The atmosphere of the sun, the corona, reaches temperatures ranging from 500,000 degrees Celsius up to six million degrees. It is basically exposed how this crown is heated and there are certainly a lot of energy inside the Sun that rises to the surface by magnetic fields. But about the mechanism of transporting heat outwards, there is no agreement among experts. Although the star with telescopes in space and on earth is observed, physicists can not directly measure many crucial properties. The sun has a lot to offer to scientific research.
The shape of the universe
The universe is expanding like a balloon that swells, and galaxies go far away from each other. So it continues until, a sufficient mass, the gravitational pull would at some point start to retreat and compress again. If there is not enough mass in the cosmos, the expansion never ceases. 14 years ago, the great scientists were surprised: the expansion of the universe, instead of slowing, is accelerating. Data overcame initial skepticism, and to the extent, considered sensational discovery, that the last Nobel Prize in Physics was. It has been called dark energy, but nobody knows what is acting to produce this accelerating expansion.
The best explanation for many is the logic that Einstein proposed, and although it would be "a property of the vacuum stretch spacetime", it could also be a new kind of force, something called the quintessence of the universe.
The possible origin of matter
The Higgs boson is a particle that has not been detected, but it has been theorized. Years of research have not been sufficient to find, but there is speculation that its function seems to be very important, as it forms the mass of everything in the universe. This theory has been proposed by the Standard Model of physics and its name comes from Peter Higgs, a British physicist who became famous for offering a possible answer to the origin of mass in the elementary particles.
Evaporation of black holes
The theory about black holes notes that these are a portion of space whose characteristic is its powerful ability to absorb energy, because inside concentrates a dense mass that causes a portentous gravity . In this regard, the scientist Stephen Hawking, in collaboration with experts in the field, argues that so-called black holes evaporate gradually losing radiation.
According to current estimates, only 4.6% of the universe is ordinary matter, atoms and particles that make up everything we see. 72% is dark energy, and 23% is much clearer: it is called dark matter. It does not absorb or emit light in any wavelength you look, but manifests its presence by its gravitational effect, especially in galaxies. According to one theory, dark matter would consist of unknown elementary particles, heavy in mass between a thousand times that of the proton. But observations, calculations, assumptions and simulations do not fit all; and another option is that dark matter is warm, with equally unknown particles but with a mass of a few millionths of the proton. To find answers, there are several initiatives, such as the observation of galaxies and structures that they form.
To describe the universe one needs to know what's in it and where its components reside. Not only dark energy and dark matter resists. More than half the baryonic matter, protons and neutrons of ordinary atoms, the stars, planets, gas and dust in the universe remains to reconcile the balance. Cosmologists have calculated the density of baryons in the early universe, and though the cosmos has changed a lot since then, the same amount should be in the present. But the current count does not house: galaxies account for 10% of baryonic matter; another 10% is the intergalactic gas and 30% is in the cold gas accumulations in space. Physicists suspect that 50% of missing baryonic matter is in the form of a hot, diffuse intergalactic plasma.
Stellar explosions. Stars are born, live and die. And their fate depends on its mass. But the fuel, hydrogen, is over. If the star is at least eight times more massive than the Sun, when the reactor is turned off, it sinks; It is formed in the center of a compact neutron star and the shock waves generated in the process make to shot out the outer layers in a new explosion that can outshine the galaxy that hosts it. If the star is even more massive it will form a black hole at the end. Another possibility is that two stars are orbiting around each other and draw material from neighboring until it collapses and creates a brilliant explosion. But these processes has many unknowns.