Download Origin of the Universe and of the Solar System

THE UNIVERSE AND
OUR SOLAR SYSTEM
Big Bang Theory
To day of today, the more accepted theory of the creation of the universe is the one of the Big
Bang. She was propose by the astronomer Lemaitre in 1927 and developed by the physicist
Gamor in 1948. According to this, the universe was created in the following order:
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1º At the outset, the matter and the space were concentrated in a same point (primigenius
atom), with a density and temperature that had of being very high.
2º Suddenly, the atom primigenius expanded abruptly in a great explosion that initiated the
expansion of the universe. The energy moved away in all directions and it was transformed
into matter (by means of the theory of relativity). Simultaneously that formed the matter,
was originated the space and the time.
3º Started to form subatomic particles later and the simplest atoms: hydrogen and helium.
4º The temperature was descending as the universe expanded. The matter expanded in all
the directions went away condensing and were appearing all the astronomical structures:
nebulas, galaxies, stars, planets… In stars, from hydrogen and of helium, by means of
processes of fusion, they appeared the different chemical elements.
Our Solar System
The Solar System is a planetary system of the galaxy Via Láctea, that is in one
of the arms of this one, known like the Arm of Orion.
According to the last estimations, the Solar System is situated about 28
thousands year-light far to the center of the Vía Láctea .
Is formed by an only star called Sun, that gives name to this System; eight
planets that orbit around the star: Mercury, Venus, the Earth, Mars, Jupiter,
Saturn, Uranus and Neptune; plus a set of other smaller bodies: dwarfed
planets (Pluto, Eris, Makemake, Haumea, Sedna and Ceres), natural
asteroids, satellites,… as well as the included/understood inter-planetary
space among them.
The Solar System
Origin of the Solar System
At the time of explaining the origin of the Solar System, this must explain certain facts:
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The Sun and the planets turn in he himself sense.
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The planets cross orbits almost circular and located in a same plane.
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The tumbling of most of planets takes place in himself sense that the translation.
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The planets next to the sun are small and dense. External, great and the dense
ones.
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All the planetary bodies present/display great impacts.
The theory of planetesimals is able to explain all these facts and is accepted at the
moment.
Planetesimals Theory (I).
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It was conceived by astronomers Weizsacker and Kuiper between 1944 and 1950. It
proposes that the Solar System has formed makes 4500 million years before, from
the gas and the dust of a nebula located in the Vía Láctea.
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1º 5000 million years before the materials of the nebula began to shake and to
interact, due, probably, to the shock wave produced by the explosion of a next star.
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2º Like consequence, most of the matter of the nebula was condensed and begun
to concentrate itself the future in the central part of system. The enormous
gravitational force of this central mass was compressed and warmed up until its
nucleus reached sufficient temperature like initiating the thermonuclear reactions
that cause that the stars emit great amounts of light and heat. It was the birth of
the sun.
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3º The intense solar emissions “blew” expensive to the space a good part of matter.
The rest remained turning around the new star, due to its gravity, until forming a
flattened disc.
Planetesimals Theory (II)
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4º In this, the densest materials were located near the center. Later, in the matter
disc, called concentrations appeared planetesimals, that they arranged in different
orbits around the sun and that they began to collide to each other, destroying
themselves and becoming to join later in greater bodies, with greater capacity of
gravitational attraction on the loose matter of their scope. Thus, the planetesimals
were the germ of future planets.
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5º the planets that formed near the sun, from denser materials, originated rocky
inner planets; those that were condensed more far from the sun, with light
materials became rocky outer planets.
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6º Later, the planets cooled off and created an atmosphere with the released
gases, that single were retained in the planets that had an important gravity.
Planets
Mercury
It presents/displays a great amount
of similar craters of impact to those
of the Moon, great lava plains and
numerous extended and straight
escarpments, possibly originated as
a result of the contraction undergone
when cooling. It has a magnetic body
of very little intensity. It does not
count on a true atmosphere: single
plans of sodium and potassium.
Venus
The atmosphere is formed by great
amount of CO2, small proportions of
nitrogen and minims amounts of
water. The existence of as much CO2
creates an enormous effect
conservatory, that causes in its
surface temperatures of around the
500 degrees Celsius. Its geologic
dynamics presents/displays
similarities with those of the Earth.
Earth
The atmosphere has a considerable
proportion of oxigen. The privileged
position within the Solar System
(intermediate) does that present
ideal conditions for the life: average
temperature of 15 ºC and abundant
water in liquid state.
Mars
The atmosphere, very dynamic
(great changes of temperature, forts
winds and storms.) are composed by
a 95% of carbon dioxide and a 5% of
nitrogen. It has water in ice form in
the polar caps, and the South
hemisphere is full of craters. Is called
the Red planet, by the iron oxide
dust that it has in suspension.
Jupiter
Gaseous planet (81% of hydrogen
and a 18% of helium) with a small
solid nucleus. What we see of they
are clouds. The strong rotation
causes that the atmosphere turns
very fast and forms parallel bands to
its equator. It emits more energy
than the one than it receives from
the sun. This, together with that it
has 16 satellites, causes that its
scope remembers us to sist to pave.
Saturn
The atmosphere is of hydrogen and
helium, although this last one is in
smaller proportion than in Jupiter
(6%). What it emphasizes more in
are thousand of ring, formed by ice
particles whose variable sizes can
have from several meters to
millimeters. This planet
presents/displays 17 satellites.
Uranus
Thinks that it consists of three
envelopes: nucleus (formed by rocky
elements), a watery envelope and
atmosphere (composed of hydrogen,
helium, ammoniac and they put) One
of more significant his caracteristics
is than the inclination of its spin axis,
with respect to the rotation plane, is
of 98º. It has nine ring of very dark
materials and fifteen satellites.
Neptune
Planet similar to Jupiter: the
atmosphere is composed by
hydrogen and helium, and
presents/displays great eddies that
turn at different speeds. It has four
ring, with particles similar to the
Saturn ring. Some of these rings
has irregular distribution. This planet
counts on eight satellites