Nebula

Nebula

Nebula in Latin is means fog. Nebula is celestial body that almost like lump of cloud that consists of gas and dust, found between the stars.
In universe is many found the spreading of nebula or fog. Fog in universe can be grouped into two kinds:

1. Milky way nebula, it is called like that because that nebula lies in Milky Way galaxy.
2. Outer Galactic Nebula, that is nebulas that exist beyond Milky Way, but that nebula is not equal to gas fog and dust fog that is found in Milky Way. That nebula consists of billions of stars, then it is called the outer galaxy.

Nova and Supernova

Nova and Supernova

Nova means a new star, it is called like that because that star is formerly not observable, then it appears and its light is very bright. The result of research of astronomers shows that Nova and Supernova are not new stars, but they are exploded star so they discharge very bright light.

The first event of Nova was happened on July 4th, 1054, in era Sung dynasty in China. In that era, it is seen a very bright star, so it can be seen in the daylight. Note shows that star lies in constellation of Taurus.

After two years, the star is not seen. Since the creation of modern telescope that is equipped by detectors devices, astronomers see a developing fog in the former place of Nova and Supernova are formed in year 1054. this fog is called crab fog. An American astronomer named Virgima Trimble measured that crab fog developed of velocity 1450 km/sec. he also can predict that all of fog united in their center of about 900 years ago. By using radio telescope is known, that crab fog is strong emitter of radio news.

Milky Way Galaxy

Milky Way Galaxy

Milky Way galaxy is in the beginning assumed to have the shape of giant gas ball that rotates in its axis. Because of its rotation, the shape of Milky Way galaxy is like a disc.
Prof. Kapteyn (1851-1922), a Dutch astronomer argued: Milky Way consists of one big set of stars, that collection has shape like a disc, our sun with its planets, they are fond in one center point of the disc.

Around the center of disc is found the collection of dense stars. The farther from the center, the looser the crowd of stars, but there is no definite outer border.

In 1917, Saphley from Harvard observatory in America, he found that Milky Way galaxy has diameter of about 1,000,000 light years and our sun lies rather to the side of center of galaxy that has distance of about 30,000 light years.

From the result of research, Milky Way galaxy consists of:
1. Star with its planets.
2. Gas fog, for example Nebula Orion, this fog looks shining because of the light of the star its absorbs, which then is emitted again.
3. Dust fog, that is the collection of fog that it can cover some part of Milky Way, such as black part found in the center of Southern Cross constellation. That dark part by sailor is called Coal Sack.

The numbers of stars in Milky Way galaxy is estimated more than 100 billion, while the number of gas fog and dust fog is almost equal to the number of star. Therefore the mass of Milky Way is predicted equal to 200 billion times of Sun’s mass.

According to the prediction of astronomers, in Milky Way galaxy is not only planet Earth that has life. But until now is not found yet its signs.

The characteristics of Milky Way galaxy are as follows:
1. Its shape is like disc.
2. Its middle part is thick and getting thinner to every direction.
3. It is found in our solar system.
4. In the middle part of disc is found about 80 billion stars.
5. In its edge part is found about 20 billion stars.

Galaxy

Galaxy

Galaxy is a group of stars in universe that their amount is large.
If we go out of house in the bright night and doesn’t cloudy also free from the influence of moonlight, then we can see on the sky a light path like giant belt that makes circle. If we observe by using telescope, the light path is union light of billion of stars even more, that lie in one group of certain galaxy. In universe, besides found billion of stars, there are also billions of galaxy, even more. But that we know is only several, including Milky Way galaxy.

Before telescope was found by Galileo-Gelilei (1610), the mistery of galxy is not uncovered yet, so several nations describe galaxy as white light.

For example people of ancient Greek described galaxy as spilled milk in the sky when Juno brestfeed her baby that has name Hercules. It is different with tales of another nation that describes galaxy is the place of dead spirits. Even some describe that galaxy as road for dead spirits to go to their lasting place.

The characteristics of galaxy are as follows.
1. It has its own light.
2. It has core that light in the center, so it is easily recognized.
3. It has certain shapes.
4. the location between one galaxy to another galaxy is very far.

The Shape of Galaxy

Based on its shape galaxy is separated into three:

1. It has shape of Ellipse

The special characteristic of this galaxy is in the middle is found pile of dense stars and have shape like lens ball, middle part is thick, while its edge is thin. The number of galaxy that has shape of ellipse is about 75% of galaxies ever recognize.

2. Spyral shape

The shape of this galaxy is like giant fire whirlpool. Milky Way galxy is included into this shape, while our Sun lies at one middle of that spyra.

3. It has irregular shape

This shape appears like small balls that spread irregularly, without striking edge.

Constellation

Constellation

Constellation is a group of star that its amount is a little and usually given names base on their shapes.
We have already known names such us Scorpio, Librana and so on. Those names often we find in the column of horoscope in magazine or newspaper. That name is actually the name of constellation. The number of constellation that lies near to Earth is 12. besides names of those constellations, there are still another names such as: Ursa Major Constellation (big bear), Gemini constellation (the twin child), Hercules constellation (man of half god). The number of all constellations found by astronomers is 88.

Usually the name of constellation is taken from the name of figure in ancient legend. But every nation imagines the figure formed by that group of star according to their own imagination. For example Scorpio constellation is imagined by people of ancient Greek as Scorpion star.

Basically constellation in universe is found in two places:


1. in south hemisphere of celestial sphere

Consist of Centaurus (involves stars of Alpha Centauri and Betha Cenaturi), Virgo (that involves Spica star), Argo (involves Canopus star), Canis Major (involves Sirius star), and Orion (involves stars of Rigel and Waluku)


2. In north hemisphere of celestial sphere

Consists of constellation of Ursa Major, Aurigia (involves Capella star), Leo (involves Regulus star), Bootes (involves Arcturus star), Libra (involves Wega star), and Siginis (involves Deneb star).

The Method to Measure Temperature of The Star

The Method to Measure Temperature of The Star

How can astronomers measure the temperature of a star?The questions often makes we think, it is remember the distance between star with Earth is very far, especially human ability is limited. Until now, human is not able yet to make plane that it can land on one star of universe’s inhabitant. Although astronomers using big telescope in observing a star, but the star observed is only seen as point of weak light.

Astronomers measure the temperature of the star by using big telescope, because the larger telescope the larger its power of magnification. Star can be photographed by using telescope, the light of the star is gathered by lens in its focus that is completed by film. Eventhough it has been magnified by complete device, often the light received by telescope is still weak, then required longer time for photography. For it can be learned carefully, the light of the star is refracted by prism, the refracted light is called spectrum.

The decomposition of light through the glass prism becomes spectrum is very important in determining temperature of a star, because large or small of star’s temperature can be observed through the decomposition of light color of that star. So the color of the star can be made reference to determine degree of high and low of star’s temperature.

For example, star that has red color is usually its temperature is less hot, on the contrary yellow color means hot and bluish white color is hotter than the colors of red and yellow. So astronomers, in determining the temperature of a star, they do not only use telescope, but they use measuring device and make calculation by using computer.

Base on its volume, the star in universe is divided into three kinds those are giant star, medium star and dwarf star.

Star

Star

Star is celestial body that has its own light and consist of flaming gas. Space between one star to another star, is not empty space, but the collection of gas mixed with dust. That collection of gas and dust does not break because atoms in outer part is attracted to inside. Its attracted of outer part atom to inside is caused by the difference of gravitational force, that gravitational force of atom that is found inside is larger. As the effect of attraction of outer part atom to inside, the collection of gas and dust wrinkles and becomes dense, so temperature inside is high also that densing collection of gas and dust begin to emit light. This is forthcoming of a star called protostar.

Temperature in the center of protostar is higher, when it reaches 10 billion degree Celcius, it happens nucleate reaction where hydrogen is changed to be helium. The longer temperature in protostar increases and causes pressure, so the protostar does not wrinkle anymore, because the pressure inside is able to support the pressure of heavy outer part. If that process has happened, a new star has born.

The Occurrence of Universe

The Occurrence of Universe

Universe is gathering place of celestial bodies that its area cannot be measured. To measure the area of universe, formerly we must measure area of each celestial body. This is not possible, because the celestial body that occupies the universe is so many like grain of the sand along the beach. The celestial bodies consists of: star, nebula, and solar system.


The happening of universe can be explained by three theories are as follows:

1. The Theory of Constant Condition

According to this theory, the universe always expands with constant velocity and formation of new materials keep going on, so in certain space is always found the equal number of materials. This theory does not know explosion to the center of universe.

2. The Big Bang Theory

According to this theory, the universe comes from horrifying explosion and galaxy will spread without limit, also that galaxy never comes back to the center of the universe.

3. Swaying Theory

According to this theory that all materials move away each other and come from the dense mass. Continuesly, that material its movement is slower then it stop and begin to crinkle again as the effect of gravitational force. Then the material will be dense and explode again. In this process there are no material that is destroyed or created, but only change in order.

The Effect of Earth’s Rotation

1. It happens daylight and night.
2. It happens false revolution of celestial bodies, for example the circulation of the sun from East to west.
3. The bending of wind direction.

This corresponds with the contents of Buys Ballet’s law, that says:
1. Air moves from the maximum air pressure to region that has minimum air pressure.
2. In north hemisphere, the wind turns to the right and in south hemisphere to the left.

To be able to prove the motion of rotation is necessary done experiment. In the following are experiments that prove the presence of earth’s rotation.

1. Experiment With Falling Body

If you falls a body from a high place and the Earth does not rotate, the body will fall directly to the center point of the Earth. Because the Earth makes rotation then that body falls a little to the east from the center point of the Earth. Experiment with falling body is first time done by Benzenberg (1802).

2. Experiment by hanging Bullet in the Peak of Tower

If the Earth does not rotate, the bullet hung in the peak of tower will precisely fall in point B. Because all bodies on the Earth and its atmosphere follow to rotate, then rotational velocity at point A is larger than rotational velocity at point B. Body fallen from a point will follow rotational velocity of its origin place. So the bullet will also follow rotational velocity at point A. Meanwhile that bullet also through distance AB, tower has slided to east direction until A’. The distance of A-A’ is larger than B-B’ ,therefore bullet does not fall in B’ but in C that its location is to the east of point B’.

Lunar Eclipse and Solar Eclipse

Lunar Eclipse and Solar Eclipse

Lunar Eclipse

Lunar eclipse often happens if Moon is in the position of opposition and lies in one knot so Earth’s umbra covers Moon, then it happens total lunar eclipse. On the contrary, if the moon lies around knot, so he Earth’s penumbra covers Moon, then it happens penumbra lunar eclipse.

Basically, the lunar eclipse is divided into three kinds, those are penumbra, partial and perfect lunar eclipse.

Solar Eclipse


Solar eclipse happens when it happens dead moon or new moon and in the position of conjunction.

There are three kinds of solar eclipse, those are as follows:
1. Total Solar Eclipse, it happens as the cause of core shadow of the moon falls to the Earth.
2. Partial Solar Eclipse, it happens if that covers Earth is only penumbra.
3. Ring Solar Eclipse, it happens if the Umbra of the Moon does not arrive to the Earth’s surface and sun appears as white ring around black ball.

The longest solar eclipse happened in 1955, it happened for 7.2 minutes that passed Sri Lanka, Thailand and Philipine.

Moon’s Aspect

Moon’s Aspect

Moon’s aspect is the position of Moon to the Sun and that can be seen there are three kinds:

1. conjunction that is the position of Moon in parallel to the Sun and lies between Earth and the Sun. In that position Moon’s surface that faces to Earth does not get light (dark), in certain condition will happen new moon or dead moon and it can also happen lunar eclipse.

2. Opposition is the position of the Moon in opposite to the Sun, if it seen from Earth, tat time the Moon appears as full moon. In certain condition it can happen lunar eclipse.

3. First quarter is Moon occupies position perpendicular to connector line of the Earth and Sun. This aspect of first quarter causes bright part of the moon is only a half, and the bright moon lies in the west. Second quarter is half part of the Moon that bright faces to the Earth and the half position of moon that bright lies in the east.

Satellite

Satellite

Satellite means follower. That is meant by the term of satellite here is celestial body that becomes follower of the planet. In this part will be discussed about natural satellite, that is satellite formed naturally, together with the formation process of the planet. Because its mass is smaller and lies in gravitational environment of certain planet, the satellite revolving the planet.

Recently, the term of satellite is used also for man-made thing that is orbited revolving our Earth. The second kind of satellite is called artificial satellite.

Almost every planet in our solar system have satellites, except Mercury. Venus and Asteroid. Our earth has one satellite called moon. Between one planet to another in our solar system has different amount. Moon’s satellite has enough influence to the life on Earth, for example has influence to large-small of sea tide.

From the result of research, Moon’s surface is not flat surface like we see from the Earth in full moon, but it has many mountains and full of craters. The condition does not mean in the Moon is many found volcanoes, but because many meteors has no atmosphere like Earth. One function of Earth’s atmosphere is protection Earth form celestial body that will fall, like meteor.

Meteor

Meteor

In the discussion about meteor, we know three terms:
1. Meteoroid is a dense celestial body that flies irregularly and it has no fixed orbit.
2. Meteor is a meteoroid that enters into the Earth’s atmosphere.
3. Meteorite is a meteor that enters into Earth’s atmosphere in the form of rock and some of them have been broken.

Meteor is a very small cosmic body that is usually called dust, sand or sky grit. If those bodies if pass to close to the Earth and enter to the Earth’s atmospheric layer, it will rub against with the air layer so that body will be hot and burnt. Burning commonly does not happen for long time because the material of the cosmic body is not large. That’s why the light of meteor immediately turns off.

Although commonly the meteor has small size, but some meteors are large enough that are not burn at all during passing through the air and some part can reach the Earth. Some meteors have very large size called giant meteor such as one that fell in Siberia, United States, Russia, and in Arizona.

The kind of Meteoric stone (Meteorite):
1. Stony meteorite, that is meteoric stone that much contains calcium and magnesium.
2. Iron nickel meteorite, that is meteoric stone that contains iron (90%) and nickel (8%).
3. Toctitt, that is meteoric stone that contains kiesel acid (80%). This kind is found spreading from back India until Peru. The specific weight of Toctitt is about equal to the specific weight of the moon. So it appears assumption that toctitt comes from the Moon that is exploded by Moon’s volcanoes when there are still volcanic activities there.

Asteroid

Asteroid

Asteroid or planetoid is a group of small planet that revolving the sun and lies between Mars and Jupiter.Base on to its shape asteroid is divided into 2 parts:
1. Large Asteroid, for example: Cars, Pallas, Vesta, Hygiren
2. Small Asteroid, for example: Eros, Hitos and Geografos.

The coagulation of glowing fog or planetesima or protoplanet, it does not only produce eight planets, but also its satellites. Asteroid also comes from planetesima.

Some small planets have diameter of 1 km, another mostly as large as moon. Asteroid that is the first time found by a Sicilian Clergyman in the first day of 19th century, that is Asteroid of name Ceres, the name of holy person and protector for Sicilian.

In the beginning asteroid is assumed only one. But, in the years later obviously is found 3 other asteroids and keep growing, until now it has been listed more that 2.000 asteroids. Its orbit is not only between Mars and Jupiter. There are asteroids are closer to the Earth than to Mars and some other are further than Jupiter measured from the Sun, such as Icarus and Apollo. That orbits around Jupiter’s orbit is called Troya asteroid. The main path of asteroid is called asteroid belt.

New Planet Found in Solar System

New Planet Found in Solar System

New planet found in solar system is called Sedna. Sedan is first time seen on date of November 14th, 2003. sedan that is formerly called 2003 VB12 it is farthest celestial body that is found orbit to the sun. its distance from the sun is predicted three times farther than the distance of Pluto – Sun.

Although Sedna can be made object of Kuiper’s Belt, or it can also be called a planet, but its discoverers until now are still not sure about that thing. Some astronomers even suppose the object as Oort cloud that is just first time detected. The Oort cloud theoretically is the icy object that because of one reason can be comet.

Several years later, mainly after presence of shopisticated telescopes, several celestial bodies have been success found in the edge of solar system. For example the Quaoar, it is found in year 2002, it is an object with diameter of about 1,200 kilometers, Izion, its found in year 2001, its width is 1,065 kilometers. Meanwhile Varuna, it is found in year 2000, it has diameter of about 900 kilometers.

Recently, astronomers detect an object named 2004 DW, that is predicted it has section size of 1,800 km. Those discoveries have turned on debate about the definition of planet, because the objects found lies in category between planet and another celestial body of smaller size.

Until now, several scientists even still assume that Pluto is not a planet, but one of the biggest minor object in the edge of solar system. So, they who assume that Pluto is not planet, certainly reject the status of Sedna as planet also. But they who assume that Pluto is a planet, perhaps he must assume that Sedna as the tenth planet because it is not far different with Pluto, especially if it is true that it has moon.

The Discovery of New Planet

The Discovery of New Planet

Astronomers have found the kind of recent planet that has similarity to the Earth. Those new of planets are predicted many found in the universe. The new kind of planet has characteristics they are included the most dwarf planet class that ever detected, their distance is less than 50 light years from the Earth. The new planet found is larger than Neptune and its circulatory period is very short.

Planets found beyond our solar system are:

1.Gilese 436
This planet lies in Leo group, its distance is 33 light years form the Earth.

2. Planet 55 Canory,
its characteristics:
a. orbits to a yellow star.
b. mass size is 18 times of Earth.
c. it has revolution period = 281 days.
d. its distance about 41 light years from the Earth.
e. it lies in cancer groupo.

Planet 55

Those two planets are found by using telescope in W.M. Keck observatory in Hawaii, Lick observatory in California and Mc.Donald observatory in Texas.

Saturn, Uranus & Neptunus

Saturn, Uranus & Neptunus

Saturn

Saturn is second largest planet after Jupiter and one inner planet in our solar system that has ring.

The ring is a lump of ice. Its revolution period is 30 years, while its rotational period = 10.02 hours and its distance to the sun is 1426 billion km. Saturn has more than 20 satellites and among other are Titan and Enceladus.

Saturn has 3 ring layers, so Saturn is planet that most beautiful compared with another planets. Those three rings are:
1. Ring A (outer ring), its diameter is 260,000 km.
2. Ring B (middle ring), its average diameter is 152,000 km.
3. Ring C ( inner ring), its diameter is 160,000 km.

Uranus

The characteristics of Uranus are:
1. Its axis is upright.
2. Its poles face the sun.
3. Its rotation is slow, so its often parallel to its orbit path.

Neptune

This planet is found by John.C.Adam in century 19. its rotational period is 15 hours, its revolution period = 165 years, its distance to the Sun = 4493 billion km, and it has two satellites those are Trition and Nereid.

The diameter of Triton satellite = 14,000 km and it has atmosphere, its shape is almost like Pluto. Meanwhile the diameter of Nereid is about 2000 km. its location if farther than Neptune if compared to Triton. Neptune is called as twin of Uranus. The condition of Neptune is denser than Jupiter and Saturn.

Mars and Jupiter

Mars and Jupiter

Mars

Mars is know as red star, its atmosphere is very thin, its distance to the sun =  226 billion km, with its revolution period is 887 days, while its rotation = 24 hours, 37 minutes, 23 seconds. Mars has two satellites those are Deimos, satellite that rises in west and sets in east.

The Natural condition of Mars:

1. Its average temperature is cooler, this is caused by its atmosphere is very thin.
2. It has volcano, ravine and wide crater.
3. Its pole is in form of terraces and covered by ice.

Jupiter

Jupiter is largest planet in our solar system. The rotation of its atmosphere is very slow if compared with the rotation of Jupiter itself, so it causes red spot around its atmosphere itself. The distance of Jupiter to the Sun is 778 billion of km, its revolution period = 23 years. Meanwhile its rotational takes time is 10 days. The space shuttle that observes Jupiter among other are: Pioner 10 and 11, and Voyager 1 and 2.

Until now, Jupiter is known has more than 30 satellites and several of them are: Ganymede (largest satellite of diameter 130,000 km), Io, Eruopa, Callisto, Amathea, Leda, Himalia, Elara, Lysthea, Anare, and Pasphipae.

Mercury and Venus

Mercury and Venus

Mercury

Mercury is one planet that lies near the sun. the distance of Mercury to the sun is about 58 billion km, while its revolution period is 88 days and its rotational period is 59 days. On date of March 29th, 1974 the space craft of Mariner 10 success to make approach with Mercury until it reach the distance of 750 km and make a picture the surface of the planet that is full of craters and basins.

It is seen from the Earth, Mercury has shape change like the moon. This condition happens because the Mercury lies at the internal part of Earth’s path.

When the Mercury passes the surface of sun, the planet is seen like spot, small forest that hangs in the middle of shinning of sun’s surface. The condition will happen only for several hours.

Venus

Venus is known as east star or evening star. It is called that because the Venus rises several times before the sun rises around 4 o’clock in the morning and several times before the sun sets 5 o’clock in the evening.

 The Natural Condition of Venus:

1. Its atmosphere has property of greenhouse that is heat received from the sun can not refract out from its atmosphere.
2. Its average temperature is 477 Celcius.
3. Its tophography is in form mountain with the formation of old and young.
4. The composition of its atmosphere consists of carbondioxide and a little amount of nitrogen also water vapor.

Inner Planet and Outer Planet

Inner Planet and Outer Planet

Inner Planet

Planets that their average distance to the sun are shorter than the average distance of Earth-Sun are grouped as inner planet. The planets that is included into this group are Mercury and Venus.

Because of circulatory velocity of the planets are different, the position of inner planet seen from the Earth changes. The change of position is described in the change of angle formed by line that connects Earth-Sun with Earth line inner planet. The angle called elongation of inner planet its size changes.

Inner Planet as Morning Star and Night Star

The elongation of inner planet is separated into west elongation and east elongation. An inner planet is called making west elongation if its position in celestial sphere seen from the Earth lies to the west part of the Sun. if its position is to the east of the Sun, it is called making east elongation.

Inner planet that is making west elongation will formerly rise compared to the Sun. It will reach east horizon when the sun still lies under horizon. At that time, the planet has opportunity reflects Sunlight directly to the Earth. Planet is seen as star in the morning (morning star)

Inner planet that is making east elongation will reach east horizon in the morning, after the sun lies above the horizon. Therefore, in the position of east elongation, the inner planet cannot be seen above east horizon. It has opportunity reflects sunlight to the Earth and it will be seen as night star, several times after the sun sets.

How long is the inner planet seen as morning star or night star? This condition very depends on the magnitude of elongation of the inner planet. The larger elongation, the longer that planet is seen from the Earth. Based on its magnitude of maximum elongation can be calculated how long Mercury and Venus are seen from the Earth.

Outer Planet


Planets that their average distance to the Sun is longer compared with the average distance of Earth-Sun are grouped into outer planet. The planet included into this group are planets of Mars, Jupiter, Saturn, Uranus, and Neptune.

The position of outer planet seen from the Earth, as also the inner planet, they are always changes. The transformation is reflected in the changes of elongation of outer planets.

The Member of Solar System, Part.2

The Member of Solar System, Part.2

The member of solar system consists of: Sun, planet, asteroid, comet, meteor and satellite.

1. Sun => click here

2. Planet


Planet comes from the world planetair (Greek Language), that means adventurer. The general conference of International Astronomical Union that is carried out in Praha city, Ceko, on date august 24th, 2006 to produces a new definition about planet.

Planet is celestial bodies that orbits the sun, that has round shape and the only dominant object in its orbit.

From the result of the general conference of IAU in praha, a number of planet in our solar system becomes eight. Pluto that formerly is included planet found in our solar system, now it is not included anymore. That thing because Pluto is assumed not big planet, but dwarf planet. The reason that Pluto is not assumed as planet in our solar system is because around orbit of Pluto is many found objects of the same kind in the form of TNO (Trans Neptunion Objects).

TNO is an object of solar system that orbits or passes beyond orbit of planet Neptune.

Meanwhile the characteristics of planet according to International Astronomical Union are as follows
a. It orbits the sun.
b. It has enough mass for its gravitational force.
c. It has eliminated another objects around its orbit.
d. It has no light source.
e. It has satellite.

If we consider the characteristics of the planet, the Pluto is not included planet, but it is a dwarf planet.

Meanwhile the characteristics of dwarf planet are:
a. It orbits the sun.
b. It has the shape of almost round.
c. It has enough mass for its gravitational force.
d. It has not eliminated yet another objects around its orbit.
e. It is not satellite.

From the characteristics, celestial body in our solar system that included dwarf planet involves Pluto, cares and xena. Meanwhile charon is not included into the group of dwarf planet, because it is satellite of Pluto.

The Member of Solar System, Part.1

The Member of Solar System, Part.1

The member of solar system consists of: Sun, planet, asteroid, comet, meteor and satellite.

1. Sun

The shape of the sun is a very big gas ball. Because it is very big, if it has shape of vessel can accommodate more than a billion of Earth planets. In our solar system, the sun roles as circulatory center of planets. To understand more, consider the following figure.

Sunlight is very dangerous for us. If we see directly, eventhough for several seconds, our eyes can be damage. The danger produced by the Sun does not come from its light, but from its heat, that is through experiment by using magnifying glass and cotton, then set that magnifying glass facing the Sun, center its light on paper or cotton in only a moment. You will see the paper or cotton is burnt.

We often think, how do astronomers learn the sun?
Astronomers in learning the Sun are helped by a device called spectroscope in their telescope. The spectroscope gives datum about the kinds of gaseous found in the Sun, and it is known that the Sun consists of Hydrogen and Helium.

Datum of the Sun:
a. the mass of the Sun = 332,448 times Earth’s mass.
b. Sun’s diameter = 1,391,000 km.
c. The distance of Sun-Earth = 150 billion km.


The Part of The Sun:

i. Core
This part is not much known yet, sun’s core is happening place of thermonuclear reaction, where hydrogen is formed to be helium and changed to be energy of temperature about 20 billion Celcius.

ii. Photosphere
The part that appears like gold disk and it has temperature about 6000 Kelvin.

iii. Chromosphere
The radiation of light that around photosphere. This chromosphere can only be seen by using telescope.

iv. Corona
The most outer layer of the sun and around chromosphere. This layer only can be seen when the occurrence of solar eclipse, and it looks like a crown.

v. Prominences
Explossions that appear beside of the sun begin from photosphere’s surface.

vi. Sunspot
Dark spot that is found in the surface of photosphere.

vii. Flare 
The part of the sun that has very luminous light and lies between sunspot.

Sun has two kinds of motion as follows:
a. Rotation revolving its axis, its period is 12,5 days for one rotation. The motion of rotation can be proved by the presence of black spots in the core that sometime lies to the right and about 2 weeks lies to the left.
b. It moves between the groups of stars. Besides making rotation, the sun moves between the group of the stars with its velocity 20 km per second. That movement is revolving the centre of galaxy.

The Movement of Member of Solar System

The Movement of Member of Solar System

The member of Solar System in revolving the sun has two movements those are rotation and revolution. Rotation, that is motion of celestial body in orbiting its axis. Rotational period is time used for one rotation. Meanwhile Revolution, that is motion of celestial body in orbiting the sun. Revolution period is the time required for one revolution.
In the below is discussed several theories about the motion of celestial bodies.

1. Geocentric Theory

This theory is stated by Claudius Ptolemaeus (in 2nd century AD), that states: “All of celestrial bodies circulate orbiting the Earth, the position of Earth in outer space is center of circulation.”

2. Heliocentric Theory

It is stated by Nicholas Copernicus, from German (1472-1543) that states: “Not earth is the circulatory center of celestial bodies, but the sun is at the center of circulation of celestial bodies.”
This theory is found in the book titled: “De Revolutionimbus Orbium Coelestium”. Because of that theory, Copernicus is given nickname that is The Father of Pioneer of Modern Astronomy. Supporters of Heliocentric theory among other are Galileo-Galilei and Issac Newton (Founder of Gravitational theory).

The content of Gravitational theory are as follows:
a. Every celestial body in this universe has gravitation.
b. Between one body to another attract each other.
c. Planets revolve the sun and do not exit from their orbit, because the presence of gravitational force.

Solar System

Solar System And Universe

Solar system is collection of celestial bodies that consists of : Sun, planet, asteroid, meteor and comet. Another celestial bodies that found in solar system move orbiting the sun so the sun is their center.

Theory of Formation of Solar System

In the following is mentioned theory that support the occurrence of solar system stated by several experts.

1. Kant’s Theory

This theory is stated by Immanuel Kant from Germany (1724-2804). According to Kant’s theory:
“That solar system comes from one gas ball of high temperature and rotates slowly. The slow rotation causes the formation of matter concentration that has high specific weight. The concentration is called core, the big one lies in the middle, while the smaller part is found around earth’s core. Because of cooling process, the core with small volume becomes planets, while the core that has big volume becomes sun.”

2. Nebular Hypothesis

This theory is stated by a French astronomer that is Piere Simon Laplace (1749-1827). According to Laplace:
“Our solar system comes from gas ball (nebula) that has high temperature and rotates fast. Because of fast rotation, some of the fog or gass ball mass escape. The part that is escaped keep rotates, because the influence of cooling longer changes to be planets.”

3. Planetesimal Theory

The theory is stated by Moulton, an astronomer, and Chamberlain, a geologist. Both are American. According to planetisimal theory:
”That in fog is found dense material that scatters called planetesimal. This dense material that then attract each other among them, because of attraction force of each part, longer big clump is formed called Planet.”

4. Riptide Theory

This theory is stated by Jeans and Jeffery (1917), both are british scientist. According to riptide theory:
“That in ancient time, near the sun, passed a big star. Because the attraction force of the star, some of sun’s mass form lump to the direction of that star. Then together with movement away of that star, that lump of sun’s mass is attracted also forms cigar, then it is escaped from the sun. the mass of gas formed then is interrupted forms giant drop with various sizes. That gas drom longer freezes forming a planet.”

5. Proto Planet Theory

This theory is stated by Carl Von Weizsaecker, G.P.Kupier and Subrahmanyan Chandarasekhar. According to Proto Planet Theory:
“That around the sun is found gas fog that form lumps and periodically becomes dense lump. The gas lump is called Proto Planet.”

Basic Principle of Plate Tectonic Theory

Basic Principle of Plate Tectonic Theory and its Relationship with Spread of Volcanoes and Earthquake

According plate tectonic theory movement of earth’s crust there are 3 kinds those are movement closing each other, movement come away each other and movement meeting each other.

1. The movement of plate that is closing each other will cause collision where one of the plate will enter under the other. The product of collision region forms of deep trough, that is usually strong earthquake path. Behind the region will be formed series of magmatic and volcanic activities also various of sedimentation basin.

2. The movement of plate moves away each other will cause rarefraction and stretching of earth’s crust and finally happens the discharging of new material from mantle forms magmatic or mountain path. Example is the formation of volcano in mid oceanic ridge in Pacific Ocean and Africa Continent.

3. Movement meeting each other is characterized by the presence of  lateral fault like San Andres Big fault in America.

The movement of Earth’s crust plate that collide each other will form sudaction zone and produces force that works whether horizontal or vertical, that it will form the fold mountain, magmatic or volcanic path, the fault of rock, and earthquake path also the formation of certain tectonic region. Besides there are also formed the various of kinds the sedimentation basin of sedimentary rock like trench, front arc basin, and the basin between the mountain and back arc basin in volcanic or magmatic path is usually formed the mining zone of gold, silver and copper, while in the collision region will be found chromite mineral. Each tectonic region has certain chraracteristic or indication, whether rock, mining, structure and its earthquakeness.

Theories of Continental Movement, Part.2

Theories of Continental Movement, Part.2

1. Plate Tectonic Theory => Click here 
2. Ed Suess’s Theory

According to Suess, the similarity of geological formation found in South America, India, Australia, and Antarctic is caused by unification of land, the united land is called Godwama Continent. The continent now is only remains because another parts of it has been swallowed by the sea.

3. Contraction Theory

This theory is created by Des Cartes. According to theory “That our Earth decreasesm wrinkles, because of cooling so that happened valleys.”

4. American Researchers Team

Researcher team that consists of 17 men from New York American Museum of Natural History, Ohio State University, and Whichita State University made research in South Pole (1969-1970) on purpose to prove Wagener’s theory. From the result of research, it is proved that South Pole 200 billion years ago lies near the equator. Therefore, it should be at that time in South Pole is found animals and plants. Continuesly, in 1969 in South Pole is found fossil of jaw bone of ancient fresh water amphibian that its shape is like salamander with characteristic its head is flat and its body is big and heavy. The kind of that fossil is found in region of South and North America. That proves theories bout movement of continents approaches truth. In that theory is explained that 150 billion years ago there was a big continent on this planet earth that is Laurasia land in north hemisphere and Godwana land in south hemisphere.

Theories of Continental Movement, Part.1

Theories of Continental Movement, Part.1

1. Plate Tectonic Theory
Plate tectonic is a theory that explains earth’s dynamic process about the formation of mountain path, volcanic path, earthquake path, and sedimentation basin on the surface of Earth that is caused by movement of the plate.

According to this theory earth’s crust (lithosphere) can be assumed as very strong raft and relatively cold that floats on elastic astenosphere mantel and very hot, or it can be equaled to icy island that floats on sea water. There are two kinds of earth’s crust those are oceanic crust that is made up of rock with base property and very base property, those are found in very deep ocean, and continental crust that is made up of acidic rock and thicker than oceanic crust. Earth’s crust covers all of earth’s surface, but the effect of presence of heat flow that flows in the astenophere caused this earth’s crust breaks to be several smaller parts called plate of earth’s crust. Therefore, plate can consists of continental crust, oceanic crust or both. That convension stream is main power source that causes movement of the plate.

In the theory is explained several analysis among others are as follows:

1. The presence of geological formation between east coast of American continent with west coast of Europe and Africa. The condition proves that geological formation in west coast of Africa is equal to east coast of America.
2. The presence of Greenland Island moves away Europe land with velocity of 36 meters per year. Meanwhile Madagaskar Island moves away South Africa as far as 9 meters per year.

According to Alfred Wegener, continents existing at it is now, formerly formed one continent. Because of the presence of big continent movement in south to west or north, it happens the following things:

1. The oceans and continents float by separately.
2. Atlantic Ocean is more larger because American continent moves to the west direction.
3. The presence of big earthquake along the fault of St. Andreas, near the west coast of United States. In 1929 Alfred Wegener died in snow at Greenland Island, when he made research to prove the truth of his theory.

The History of Earth’s Surface

The History of Development of Earth’s Surface

The shape of Earth surface is various and each of it passes difference process. The difference of the process among other are influenced by power and time. The Earth is a planet that has certain characteristic, so it enables the presence of life.

Our Earth was formed about 4.6 billion years ago together with the formation of one solar system called the solar family. One theory called Nebular Hypothesis tells the story in 3 phases:

1. Sun and another planets are still in the form of gas, it is very dense and big fog.
2. The fog rotating and twisting strongly, where the coagulation happens in the center of the circle that then forms the sun. at the same time, another material formed becomes mass that is smaller than the sun that is called planet, it moves revolving the sun.
3. Those materials grow more larger and keep doing movement regularly revolving the sun in one fixed orbit and form the composition of the Solar family.



Earth is one member planet of our solar system. The occurrence process of the Earth is equal to the sun. Because of its volume is smaller than the sun, its formation process is faster. In formation process of Earth, it happens separation base on to its mass. The heavy part forms core that is called barisphere, while the lighter part forms Earth’s crust or often called lithosphere.

In cooling process that reaches 100 Celsius, it happens condensation, then happens rain, after that the rain water fills the lower parts of Earth and forms watery layer called hydrosphere. Besides lithosphere and hydrosphere, the Earth is also covered by air layer or atmosphere and life layer called biosphere.

In carbon era, the continents unite form the big continent called pangae that in Greek means “the whole world”. Since 1900, geologists have known that outer part of Earth’s crust floats on the soft inner layer.

Classification and Branches of Geography

Classification and Branches of Geography

In broad outline, geographical science can be classified into two parts as follows:

1. Physical Geography

Physical geography is a branch of geography that studies physical phenomena on earth’s surface. Inspection field of physical geography is natural phenomena of earth’s surface that becomes human living environment.

The study of physical geography is supported by several sciences below:
a. Geology => a science that studies structure, composition, history and development process of the earth.
b. Pedology => a science that studies the kinds and formation process of soil.
c. Astronomy => a science that studies celestial bodies.
d. Oceanology => a science that studies about physical and chemical properties of sea water.
e. Climatology => a science that studies about climate.
f. Meteorlogy => a science that studies about weather.
g. Volcanology => a science that studies about volcanoes.
h. Seismology => a science that studies about earthquake.
i. Geophysics => a science that studies the properties of the inner port of the earth with physical method, such as measuring earthquake, gravitation, and magnetic field.
j. Biogeography => a science that studies spreading of living organisme geographically on earth’s surface.


2. Social Geography

Social geography is a branch of geography that covers population aspects and human activities that consist of economic, politics, social, and cultural activities.

Branches of social geography are as follows:
a. Human geography => a branch of geography that studies social economy, and culture of population.
b. Anthropogeography => a branch of geography that studies the spreading of races on earth, seen from geographical point of view.
c. Polytical geography => a branch of geography that studies geographical conditions seen specifically.
d. Regional geography => a branch of geography that studies a certain fegion specifically.
e. Population geography => a branch of geography that studies the numver, spreading, and composition of population.
f. Economic geography => a branch of geography that studies economic activities of population in a certain region.
g. Rural geography => a branch of geography that studies the condition of rural areas, including the society, from geographical point of vies.
h. Urban geography => a branch of geography that studies about urban regions, including the society, from geographical point of view.

The Scope of Geography

The Scope of Geography

Geography is a science that studies interaction between man and his environment, so geography has clear objects and scope. The object of geography basically is divided into two, that is material objects and formal objects.
The material objects of geography are geospheric phenomenan that cover several layers, they are lithosphere, atmosphere, hydrosphere, biosphere and anthorosphere. Meanwhile, the formal objects correspond to points of view on a spatial phenomenon on earth’s surface.

Formal objects are regions on earth surface that have their own characteristics, so they can be distinguished from other regions, usually based on natural and social aspects.

Formal object geography are indicators and differenciators from other sciences, while the scope of geographical study enables man to gets answer to questions from the world around that emphasize on spatial and ecological aspects. Geographical study involves the earth, its aspects and formation process, causal and spatial relation of humans with their environment, also the interaction of humans with the environment around them.

Rhoad Murphey, in his book “The Scope of Geography”, proposed three scopes of Geographical study:
(1) Geography learns the spread and relation of mankind on earth’s surface. Beside, it studies about aspects of humans’ living place also how to use it.
(2) Geography studies mutual relationship between man with physical environment (nature) as part of regional diversity study.
(3) Geography studies a regional frame and analyses a region that has specific characteristics.

From the analysis above, it is clear that the scope of geography is inseparable from natural aspects and human aspects. The meaning of environment in geography is not only limited to natural environment, but also man-made environment.

Aspects of Geography, part 2

Aspects of Geography, part 2

1. Physical Aspects => click here (aspects of geogaphy part.1)
2. Social Aspects

Social aspects of geography that can influence human life, for example are population, mobility of population, and the spread of population.

     a. Population
One social aspect that influences human life is the number of population. Large potency of population can either support or hinder development.

The potency of population that can support development among others are:
(1) Productive aged population is a source of labor.
(2) Large population can be used as developmental manpower.
(3) High quality of manpower can be used as experts.

     
     
     b. Mobility of Population
The social aspect of geography that corresponds to mobilization of population is urbanization. Urbanization influences urban and rural population. The phenomenon that we can see in urban regions as the effect of urbanization is the spread of slums and high criminality rate. Meanwhile, the phenomenon that arises in the rural areas is the decrease of agricultural productivity as the effect of losing young works.

     c. The Spreading of Population
Winder effect of uniform spreading of population are as follows:
(1) Development is not evenly distributed.
(2) Utilization of natural resources is not optimum.
(3) Agricultural land decreases because it is used for housing.

Aspects of Geography, Part.1

Aspects of Geography, Part.1

In broad outline, geography can be divided into two parts, physical geography and human geography.

Physical geography studies about physical aspects, while human –social- geography  studies about social aspects. Those two aspects have influence on the environment of human life. Physical aspects involve: earth’s relief, mineral and structure of rocks, water, weather and climate, flora also fauna. Meanwhile, social aspects involve aspects of social, politics, economy and culture. In geography, physical aspects and social aspects always relate to other sciences.

1. Physical Aspects

The geographical aspects that can influence human life is physical aspect. Several physical aspects that influence human life are, for example: climate, relief, earthquake, volcanism and so on. Certainly in geography physical aspects that can influence human life are so many, but in this discussion they are limited to several aspects.

Examples of physical aspects that can influence human life are as follows:

  

      a. Climate and its elements.

Climate is an important geographical element that can influence human activities.

Climate condition on earth’s surface varies. The factors that form of Asia region is archipelago that has four basic climatic characteristics, they are:

(1)   Annual average temperature is high.

(2)   Has two seasons that is rainy season and dry season.

(3)   High air humidity.

The influence of climate on human activity:

(1)   Fisherman start to go to sea (sail to the sea) at night, because they use the land breeze, on the contrary at day time, fishermen come back to the land by using sea breeze.

(2)   Around the months of October-April farmers from Asia start to work on their land, because in those months has rainy season.

  

      b. Relief of Earth.

 Earth’s relief is the highness and lowness of earth’s surface. Earth’s relief is a physical aspect of geography that has influence on the life of humans or plants. The following are several influences of earth’s relief on human life.

 The influence of earth’s relief on the growth of plants can be learned in Junghun’s classification as follow:

(1)   Hot Zone, 0 – 700 meters => The kinds of plants that live there are riceplant, sugarcane, and coconut.

(2)   Temperate Zone, 700 – 1500 meters => The kind of plants that live there are coffee, tea quinine, rubber, and holticulture.

(3)   Cool Zone, 1500 – 2500 meters => The kinds of plants are casuarinas tree and pine.

(4)   Cold Zone, >2500 meters => The kind of plant that live is moss.

      c. Earthquake

Earthquake, whether tectonic or volcanic, greatly influences human life. The number of times earthquake happens influenced by geological position.

The effect produced by earthquake on the life on earth’s surface is very vast, example:

(1)   The presence of tectonic earthquake can help geologists to determine the content of minerals in lithosphere.

(2)   The presence of earthquake can help architects in determining the shape of houses and materials used to build houses that are earthquake-proof.

2. Social Aspects => click here

Principles of Geography

4 Principles of Geography

Geographical principle is the foundation to analyze and disclose geographical phenomena on earth’s surface. Theoretically, geographical principles are as follow:

1. spreading Principle
Spreading principle can be used to describe geographical phenomena and facts in the map, also to express relationship between one geographical phenomenon and another. That is because the spreading of geographical phenomena and facts is not uniform from one region to another region.

2. Interrelationship Principle
Interrelationship principle is used to analyze the relationship between physical and non-physical phenomena. That principle can express geographical phenomena or facts in a certain region.

3. Descriptive Principle
Descriptive principle in geography is used to give further illustration about geographical phenomena and problem analyzed. This principle does not only show description in the form of a map, but also in the form of a diagram, graph or table.

4. Chorological Principle
By chorological principle we can analyze geographical phenomena, facts, and problems seen from their spreading, interrelationship and interaction in space.

Essential Concepts of Geography

10 Essential Concepts of Geography

Geography is basically the study about real phenomena in human life. Geographical phenomena that exist around us are the product of all spatial interrelationships between physical and non-physical factors. In learning geographical phenomena, there are real patterns and abstract patterns. Abstract patterns are in the form of abstract understanding that is called concept.


There are 10 essential concepts of geography as follows:

1. Concept of Location
Concept of location in geography analyzes the positive and negative aspects of a place on earth’s surface.

Concept of location is usually used to answer the question of where geographic location is divided in two kinds, they are:
i. Absolute location, that is location of a region based on latitude and longitude.
ii. Relative location, that is the location of a region on earth’s surface that has changing properties because it is influenced by the regions around it. Example: Land in urban area is usually more expensive.

2. Concept of Distance
Distance is a natural separator. Distance is related with location and efforts to satisfy basic needs of life.
Example:
a. Traveling distance to transport raw material to factory, influences the amount of tranportational cost.
b. Land that is located far from a highway is cheaper.

3. Concept of Achievability
Achievability is related to the condition of earth’s surface. For example: a region is isolated because its earth’s surface condition causes it to be hard to reach. Dependency commonly changes according to the development of economy, science and technology and transportation.
Example: A village that is surrounded by swamps and forest is usually harder to reach than a village that is located on the beach.


4. Concept of Pattern
Pattern is related to dependency on various geographical phenomena on earth’s surface. Geography learns about patterns of form and spreading of geographical phenomena.
Example:
a. Pattern of settlements in mountainous area is dominated by spreading pattern.
b. Pattern of river in fold regions is commonly trellis.

5. Concept of Morphology
Concept of morphology corresponds to the shape of earth’s surface as product of endogenic and exogenic powers.
Example: Low land along Java’s north coast is dominated by sugarcane plantation.

6. Concept of Agglomeration
Agglomeration is spread that tends to group in a region that is relatively narrow and most profitable.

7. Concept of Utility Value
Utility value is geographical phenomenon or natural resource on earth’s surface that is relative to each other among regions.
Example:
a. The sea has more utility value for fishermen, compared to farmers.
b. Forests have more utility value for natural lovers compared to students.

8. Concept of Interaction
Interaction is mutual relationship between two regions or more that can produce new phenomena, appearance and problems. In interaction, one phenomenon depends on another.
Example: Interaction of city-village happens because there are differences of natural potentials, for example: the village produces raw material, while the city produces industrial products. Because both regions need each other, then interaction happens.

9. Concept of Area Differentiation
Area differentiation corresponds to interregional characteristics on earth’s surface. Concept of area differentiation is used to study differences of geographical phenomena between one regional another on earth’s surface.
Example: The kinds of plant cultivated in highland will be different from the kinds of plant in low lands. Detailed examples are found in Junghuhn’s climate, for example:
a. Zone of height 0-700m, the kinds of plants cultivated are: sugarcane, coconut and corn.
b. Zone of height 700-1500m, the kinds of plants cultivated are: tea, coffee, cacao, tobacco and quinine.
c. Zone of height 1500-2500m, have plants such as pine and casuarinas tree.
d. Zone of height more than 2500m, the kind of its plants is dominated by fungi.

Besides, concept of area differentiation can also be used to see the kind of means of livelihood, for example inhabitants that live in coastal region have dominant means hood as fishermen, different from people that live in lowland who tend to work as farmers as their means of livelihood.

10. Concept of Spatial Interrelatedness
Spatial interrelatedness shows spread relationship between one phenomenon and another, both in terms of physical or non-physical phenomena.
Example:
Rural and urban areas, for example: inhabitants of urban region need foodstuff from the rural area, on the contrary inhabitants of the rural area need to market their natural products to the city.