GALAKSI Resume UK 4 English Okemen
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Transcript of GALAKSI Resume UK 4 English Okemen
GALAXY
A. Understanding Galaxies
Galaxies are clusters of billions of stars. Usually about 100 billion
stars. Galaxies have a variety of shapes such as spirals, discs, elliptical or
irregular. Galaxy where our solar system is the Milky Way galaxy (milky
way). The numbers of galaxies in the universe are now an estimated 100
billion galaxies.
Galaxy is a system bound by gravity which consists of (in all its
manifestations, such as neutron stars and black holes), gas and cosmic dust
interstellar medium, and the possibility of a hypothetical substance known as
dark matter. The word galaxy derives from the Greek Galaxias which means
"milk," which refers to the Milky Way (English: Milky Way).
B. Galaxy Formation Process
Formation and galaxy growth is expected to occur as a result of the
force of gravity between galaxies or joint sub sub galaxies that process occurs
constantly.
C. The characteristics of Galaxies
Galaxy is set by billion, even by trillion of star
All galaxies have a nucleus of the galaxy system
The entire system is contained in the galactic rotation
The galaxy has its own light, not reflected light
The galaxies are only visible outside the Milky Way Galaxy line
The distance between one another galaxy millions of light years
Galaxies have certain forms:
For example: a spiral, elliptical shape, and irregular shapes.
D. The Classification of Galaxies
According to the morphology, the galaxy is divided into 3 types,
namely spiral galaxies, elliptical galaxies, and irregular galaxies of this
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division is based on the shape or appearance of galaxies - galaxies. Galaxies
were observed and studied by astronomers so far consists of 75% spiral
galaxies, elliptical galaxies 20%, and 5% irregular galaxies. But this does not
mean that spiral galaxies are the most numerous galaxies in the universe ini. In
fact most abundant in the universe are elliptical galaxies. If we take the same
volume of space, we will find more elliptical galaxies than spiral galaxies. It's
just that many galaxies of this type are very faint, so it is very difficult to see.
The classification are:
1. The Elliptical Galaxy
In accordance with its name, such
as elliptical appearance. But the original
form is not known with certainty because
we do not know the direction we look,
whether from front, side, or top of the
galaxy.
The Characteristics of Elliptical Galaxies
Type of galaxies range from circular to oblate spherical.
The structure of this galaxy is not seen clearly.
Looks very dim
Very few contain interstellar material.
Its members are the stars - old stars.
Kinds of Elliptical Galaxies
a. The Messier 87 Galaxy
The heart of the galaxy known as M87 is a place of unimaginable
violence. A black hole up to seven
billion times as massive as the Sun sits
at the galaxy's center -- one of the most
massive black holes ever measured. As
gas spirals into the black hole, it's
heated to millions of degrees, so it
produces enormous amounts of X-rays.
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Some of the hot gas around the black hole shoots back into the galaxy in
powerful jets that span thousands of light-years.
M87 is at the center of the Virgo Cluster.M87 contains many more
stars and is perhaps 10 times as massive as the Milky Way., it was one of
the first galaxies suspected to have a black hole, based on observations
conducted in the early 1980s.
b. The Messier 32 Galaxy
Messier 32 (also known as NGC 221 and Le Gentile) is a dwarf
elliptical galaxy about 2.65 million light-years away in the constellation
Andromeda. M32 is a satellite galaxy of
the famous Andromeda Galaxy (M31)
M32 contains a supermassive
black hole. Its mass has been estimated to
lie between 1.5 and 5 million solar
masses.
c. The Messier 59 galaxy
Messier 59 (also known as M59 or NGC 4621) is an elliptical
galaxy in the constellation Virgo. Messier 59 and the nearby elliptical
galaxy.
Messier 59's core contains
a supermassive black hole, with a mass
that has been estimated to be 270 million
times the mass of the Sun. He has an
inner disk of stars and is very rich
in globular clusters, with a population of
them that has been estimated in around 2200.
2. The Spiral Galaxy
This type of galaxy is the most common type known to people.
Most likely due to the spiral shape that beautiful. Section - the main part is
a spiral galaxy halo, including the field of the galaxy's spiral arms and the
bulge, and the central part of the galaxy that prominent. Globular clusters 3
that are forming halo with star - a star that
is not contained in the plane of the
galaxy.
The Characteristics of Spiral Galaxy
Form a beautiful spiral.
Consists of - old stars and star - a
young star.
Star - big stars are in globular clusters scattered envelop galaxies.
This galaxy is rotating at a speed much faster than elliptical galaxies.
And because the rotational speed causes the galaxy and form a
flattened galactic plane.
The rotational speed of each part of the spiral galaxies are not the
same. Increasingly towards the galactic center speed greater.
Star - starlets are on spiral arm galaxy located in the galactic plane.
The Kinds Spiral Galaxies
a. The Andromeda Galaxy
Andromeda galaxy Messier 31 with another name, M31, or NGC
224 is one of the galaxies outside the Milky Way visible to the naked eye,
as long as seen on a clear night, with
no moon and no light pollution. The
structure is similar to the Milky Way
is a spiral-shaped. The distance is
about 2.5 million light years. It's in the
sky is in the northern hemisphere sky,
about 41 degrees to the north of the celestial equator, both observed
around the month of September, October and , November.
Andromeda size can be more than 7 times the angular diameter of
the moon. This galaxy contains about one trillion stars, and moving toward
the Milky Way at a speed of about 300 km / sec.
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b. The Milky Way galaxy
Milky Way galaxy of 400 billion stars, with a diameter of about
130,000 light-years away (one light year is 9.500 billion kilometers). The
Milky Way is home to our sun and its planets surrounding it. This spiral
galaxy with an average size, and always forms a new star every year.
c. The Sombrero Galaxy
The Sombrero Galaxy (also known as M104 or NGC 4594) is an
unbarred spiral galaxy in the constellation Virgo. Has a bright nucleus, an
unusually large central bulge, and a prominent dust in a disk inclined road.
Dark dust lane and the bulge give
this galaxy the appearance of a
sombrero. The galaxy has an
apparent magnitude of +9.0, making
it easily visible with amateur
telescopes.
d. The Black Eye Galaxy
A spiral galaxy in the
constellation Coma Berenices,
Messier 64, the famous "Black
Eye" galaxy or the "Sleeping
Beauty galaxy," has a
spectacular dark band of dust in
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front of the absorbing intelligent galactic nuclei appear small
when observed with Telescope.
e. The 2MASX J00482185-2507365 occulting pair galaxy
2MASX J00482185-2507365 occulting
pair is a pair of overlapping spiral galaxies
found around NGC 253, the Sculptor Galaxy.
This pair of galaxies illuminates the distribution
of galactic dust beyond the visible spiral arms
of galaxies.
f. The Whirlpool Galaxy
The Whirlpool Galaxy is also known as Messier 51A, M51A, or
NGC 5194, the Whirlpool Galaxy is an interacting
grand-design spiral galaxy located at a distance of
about 23 million light-years away in the constellation
Canes Venatici. This is one of the most famous spiral
galaxies in the sky. Galaxies are easily observed, can
be seen with binoculars.
g. The Messier 81 Galaxy
Located in the northern constellation Ursa Major, is one of the
brightest galaxies visible in the skies of
planet Earth. This incredible detailed view
reveals a bright nucleus, a large spiral arms
and sweeping cosmic dust lane with a scale
comparable to the Milky Way.
h. The NGC 1512 Galaxy
Including the constellation
Horologium, Galaxy NGC 1512 is quite
similar to the great Milky Way. Is a
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starburst galaxy core ring, which is a remarkable circle of young star
groups that include several light years.Galaxy "starbursts" are episodes of
vigorous formation of new stars and galaxies are found in a variety of
environments.
i. The Grand Spiral Galaxy
Grand Spiral Galaxy also known as
NGC 123, this fascinating galaxy is
dominated by millions of bright stars and
dark dust, caught in a vortex gravity spiral
arms rotate around the center of the galaxy
3. The Irregular galaxy
Irregular galaxy is a galaxy type is not symmetric and does not
have a specific shape. Members of this
galaxy consists of old stars and young
stars. This irregular galaxy contains a lot
of interstellar material consisting of gas
and dust.
The Characteristics of Irregular Galaxy:
This galaxy contains a lot of material
consisting of gas interstellar gas and
dust.
Consisting of - stars old and young.
The shape is not symmetric and does not have a specific shape.
The kinds of Irregular Galaxies:
a. The Large Magellan Cloud Galaxy
Large Magellan Cloud is a nearby galaxy as well as a third one
loyal companion Milky Way galaxy in which we live. The Large
Magellan Cloud galaxy is 157,000 light-years away from our Earth.
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Mass of the Large Magellan
Cloud is only about 1% of the mass
of the Milky Way or the equivalent
of 10 billion solar masses. Large
Magellan Cloud galaxy very rich in
gas and dust, with star formation
region active in it. A number of
exotic star was found inside. For
example, Supernova 1987A.
Apparent magnitude +1 so easily seen by the human eye without
any tools.
b. The Small Magellanic Cloud Galaxy
The Small Magellan Cloud (SMC) is a galaxy. It is classified as
either a dwarf irregular galaxy or as a Magellan type dwarf spiral
galaxy. It has a diameter of about 7,000 light-years and contains
several hundred million stars.It has a total mass of approximately 7
billion times the mass of the Sun.
With a mean declination of approximately −73 degrees, it can
only be viewed from the Southern Hemisphere and the lower latitudes
of the Northern Hemisphere. It is located in
the constellation of Tucana and appears as a hazy, light patch in the
night sky about 3 degrees across. It looks like a detached piece of the
Milky Way. Since it has a very low surface brightness, it is best
viewed from a dark site away from city lights.
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