Gas planets

1.Why gas planets are far from the Sun?

Rock planets are close to the sun. But gas planets are far from the Sun. Rock planets' space is hotter than gas planets' space. So in rock planets' space, many meterials are less intergrated than gas planets' space. So Jupiter, Saturn, Uranus, Neptune is bigger than Mercury, Venus, Earth, Mars.

2.How did gas planets created?

Maybe you learned that Gas planets don't have surface that you can walk. But if we go to inner of Gas planets' atmosphere,  we can find a planet that have a liquid surface. Maybe liquid is created by gas' pressure. Liquid was maybe a gas. Maybe Jupiter,Saturn,Uranus,Neptune were rock planets. But because of their strong gravity, they have very big atmosphere. And it would became gas planets. 

Bode's law

 We learn about the Mercury, Venus and the Earth. If you want to memorize sun to planets' distance, you should know  Bode's law. Bode is astronomer that discover this law.

Let's know about planets' orbit's radius. It can apply to only Mercury to Uranus.

Mercury:0.4AU
Venus:0.7AU
Earth:1AU
Mars:1.6AU
Jupiter:5.2AU
Saturn:10AU
Uranus:19.6AU

Let's ride those radius.
0.4,0.7,1,1.6,5.2,10,19.6

Let's multiply 10 to those numbers.
4,7,10,16,52,100,196

Let's take out 4 in those numbers.

0,3,6,12,48,96,192

Where is 24? In 2.8AU from the sun, there is asteriod belt. Uranus is discovered by this law




 

The fastest planet, the Mercury.

 The Mercury is the closest planet from the sun. So powerful sunlight eclipse the Mercury, so we watching the Mercury is very hard and dangerous. This fast planet named "Mercury" because Mercury is the fastest god in Greek and Roman mythology. Mercury is simillar with moon. Because it has no atmosphere and it is desert like moon. Let's learn about the Mercury.

1.Mercury's orbital characteristic

 The Mercury is close from sun. The Mercury is about 46001272km to 69817079km from the Sun. The mercury's orbit is ellipse. It is not simillar to circle.

Aphelion:69817079km
Perihelion:46001272km

It's orbital period is about 88 days. It's rotation period is 58 days.

2.Mercury's physical characteristic

The mercury is very samll. It's surface area is 0.147 x Earth's surface area. And its volume is 0.056 x Earth's volume. And its mass is 0.055 x Earth. But its mean density isn't samll. Its mean density is 5.427 g/cm³  So it doesn't have enough gravity that it can't have enough atmosphere. So it changed desert like moon.


Volume:6.083×10¹⁰ km³
Mass:3.3022×10²³ kg
Surface area:7.48×10⁷ km²
Mean density:5.427 g/cm³


And it doesn't occurs greenhouse effect on the Mercury, so the Mercury's night is very cold.

Night mean temperature:103K
Mean temperature:440K
Day mean temperature:623K

3.Mercury's atmosphere

 It has a tiny atmosphere

42% oxygen
29% soduim
22% hidrogen
6.0% heluim
1% others




 

Our king, the Sun's characteristic

 Let's know about our king the Sun. Sun and Earth's distance is 150000000km Sun's mass is very big. Sun's greavity is so powerful that it can makes planets to turn the Sun. The sun's mass is 99.8% of whole solar system's mass. In morning, we can see bright sun over the sky. If sun doesn't exist, we can't live. Let's learn about Sun's characteristic.

1.Sun's orbit's characteristic

 Sun turns the center of milkiway 0.2 billions day a once. Its orbital speed is 217km/s.

2.Sun's physical characteristic

Mass:1.9891×10³⁰ kg(330000xEarth)
Mean diameter:1,392,684 km(200xEarth)
Volume:1.412×10¹⁸ km³        
Surface Area:6.0877×10¹² km
Average density:1.408×10³ kg/m
Sidereal rotation period:25.05 days
Rotation period at pole:34.4days

3.Sun's photospheric composition
Hydrogen:73.46&
Helluim:24.85%
Oxygen:0.77%
Carbon:0.29%
Iron:0.16%
Neon:0.12%
Nitrogen:0.09%
Silicon:0.07%
Magnesuim:0.05%
Sulfur:0.04%

The moon

 In night, we can see moon over the sky. We can't see many stars because of light pollution, but we can see bright moon. Moon is the Earth's one non-artificial satellite. Let's learn about moon's characteristic.



1.Moon's orbit's characteristic

Perigee:363295km
Apogee:405503km
Orbital period:27days,7hours,43minutes
Synodic period:29days, 12hours, 44minutes

2.Moon's physical characteristic


Mean radius:1737km
Flattening:0.00125
Surface area:3.793 × 10⁷ km² 
Volume:2.1958 × 10¹⁰ km³
Mass:7.3477 × 10²² kg 
Mean density: 3.3464 g/cm³
Minimum temperature:100K
Mean temperature:220K
Maximum temperature:230K



 

Our blue planet, Earth.

 We know Earth is round and Earth turns the Sun. 
http://travelingcosmos.blogspot.kr/2013/12/how-do-we-know-earth-is-round.html
http://travelingcosmos.blogspot.kr/2013/12/how-do-we-know-earth-turns-sun.html
 We lives in blue planet, Earth. Let's know about our home, Earth. 

1.Earth's orbit
  Earth turns the sun. How far earth to the sun? Earth's orbit's radius is about 150000000km, or 1AU. Earth's orbit is ellipse but it is nearly circle. Its eccentricity is about 0.016. Earth's Orbital period is about 365.24days, or1year. Earth's average skidding speed is about 29.8m/s.

2.Earth physical characteristics



Mass:5.97219×10²⁴ kg

Radius:6,371.0 km

Volume:1.08321×10¹² km³

Density:5.515 g/cm<sup>3

Lowest temperature:</sup>−89.2 °C


Average:15 °C

Highest temperature:56.7 °C

Surface pressure:101KPa

Compositon: 78% nitrogen, 21% oxygen 0.93% argon 0.04%carbon dioxide

How do we know Earth turns the sun?

 How do we know Earth turns the sun? We can't feel Earth turns the sun. Because human being can't feel Earth turns the sun, in 16th Century, most people believed Earth is center of cosmos. And let's know how do we know Earth turns the sun.
But, normal people can't feel Earth turns the sun. If you want to feel Earth turns the sun, you should observe sun and planets. And use data to prove Earth turns the sun.

1.Copernicus' observed data
 Why does Copernicus claim Earth turns the sun? He compared with his observed data to geocentrism. But it 
occured 8 ° error. So he compared to heliocentricism. It was 

accurate. But his data is professional,so we can't know about

it. 

2.Venus and Mercury

There is the sun, and there is the Earth. We saw, observed 

data of Venus,we can saw Venus is not more than 40 ° off to 

the Sun. So we can think Venus is located between the Sun 

and the Earth. Mercury is similar. But its angle is smaller than 

Venus. So we can think Mercury is located between the Sun 

and the Venus. And we can see Venus changes the shape 

like moon. If Venus turns the Earth, this phenomenon never 

occurs. So we can think Mercury and Venus turns the Sun.





3.Mars

Somedays, Mars is close and, somedays, Mars is far. SoMars 
turns the sun. Jupiter, Saturn, Uranus, Neptune is similar. So 
Jupiter, Saturn, Uranus, Neptune turn the sun, too. And let's prove Earth .

Sun's gravity makes planets turn the sun. So Earth turns the sun, too.

How do we know Earth is round?

 Everyone knows Earth is round. Most of the people can't fell Earth is round. Almostly, they feel Earth is square. (Everyone knows Earth is round) is only result of education. So how do we know Earth is round?

1.Boat

 Imagine that you are in port and one boat is going to horizon. And we can see that boat is a little bit going down. Earth is round, so we can see this scene.

2.Lunar Eclipse

 Do you know Lunar eclipse? Lunar eclipse is phenomena that when Sun-Earth-Moon is a straight line,Moon become obscured by  Earth's shadow. Earth's shadow's shape is round. So we can know Earth is round. 

3.Time difference

 Each place's time is different. When Korea's students go to school, London and Paris' children are sleeping. If Earth isn't round, at the same time sun is rise, and at the same time evening is coming. But each place's time is different. So we can know Earth is round. 

4. Questions

 And We may have some questions. Let's solve questions. 

1.If Earth is round, why we don't fall? 

Because of Earth's gravity.

2.Earth is turning fast. Why we don't thrown into space?

Because air is turnig same speed, too.

3.Why we can't feel Earth is round?

Because we are so small.

Families of Solar systmem

 Let's learn about families of solar system.
1.Sun
Firstly, there is king of solar system, the Sun. Sun's mass is 99.8% of whole solar system's mess. Its surfacs's temperature is about 6000 degrees Celsius. And we can see many black points on the sun's surface. It's called "Sunspots" Sunspot is area that cold than usual sun's surface.  Sunspots' temperature is about 4000 degrees Celsius. Sun's gravity makes planets to turn the Sun. Sun's gravitational field's radius is about 2 light-year.

 

2.Planets

 There are 8 planets in solar system. Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune are 8 planets. Jupiter is the biggest planet in solar system. Saturn is 2nd, Uranus is 3nd, Neptune is 4nd(But Neptune is heavier than Uranus).

This is planets' mass porpotation graph.

Bluish green is Jupiter, orange is Saturn, brown is Neptune, pale blue is Uranus. Mercury, Venus, Earth, Mars are rocky planet. It has a land that you can walk. Rocky planets are small and have big density.

And Jupiter, Saturn, Uranus, Neptune are called "Gas Giant" They are big and they are not rocky. They have lots of gas. So they don't have a land that you can walk. They have small density.

 

 




3.Dwarf planets
 Dwarf planets can keep sphere shape by its gravity, but it can't be planets. They are smaller than planets. Pluto is typical dwarf planets. Pluto was planet, but it changed to dwarf planets. Because one object that is heavier than pluto was discovered.(Eris). And many object that similar to Pluto were discovered. So we must add many palnets. So Astronomers made new level called "dwarf planet" How do we classify planets and dwarf planets? These are define of planet. If some object want to be a planet, it must satisfy does 3 conditions.

 1.Objects with true masses below the limiting mass for thermonuclear fusion of deuterium (currently calculated to be 13 times the mass of Jupiter for objects with the same isotopic abundance as the Sun) that orbit stars or stellar remnants are "planets" (no matter how they formed). The minimum mass and size required for an extrasolar object to be considered a planet should be the same as that used in the Solar System.

 2.Substellar objects with true masses above the limiting mass for thermonuclear fusion of deuterium are "brown dwarfs", no matter how they formed or where they are located.

 3.Free-floating objects in young star clusters with masses below the limiting mass for thermonuclear fusion of deuterium are not "planets", but are "sub-brown dwarfs" (or whatever name is most appropriate).

These are dwarf planets.

Pluto and its moon "Caron"
Cedna 
Haumea It's looks like a egg.
Qauoar
MakeMake



4. Asteroids

Asteroids are very small. It can't keep sphere share. They are almostly gathered between Mars and Jupiters. It called "Asteroid belt"

 

5.Comet

Comet is consisted by dirty ice and rock. Representative comet is Halley's comet. It turns the Sun. Its orbit is ellipse. When it is near to the sun, it get a big and blue tail offside of the sun.

The structure of the solar system

 We can see the sun in the sky. Our Earth turns the sun.  Sun is very heavy. Many planets turns the sun. Sun and many objects that turns the sun called "Solar system" Solar system's center is the sun. Mercury is the closest to the sun. Venus is 2nd, Earth is 3rd, Mars is 4th, Jupiter is 5th, Saturn is 6th, Uranus is 7th, Neptune is 9th.  Mercury, Venus, Earth, Mars are rocky planet. It has a land that you can walk. Rocky planets are small and have big density.

And Jupiter, Saturn, Uranus, Neptune are called "Gas Giant" They are big and they are not rocky. They have lots of gas. So they don't have a land that you can walk. They have small density.

 

 

 

And there is no big planet over the Neptune. Astros that farther than Neptune called TNOs. Over the Neptune, there are Kuiper belt, and Oortclod. In kuiper belt there are many asteroids and dwarf planets. Pluto, Haumea, Makemake, Eris, Sedna,Quaor are dwarf planets. Oort cloud is end of the solar system. Oort cloud is origin of long period  comet. Oort cloud's end is about 50000AU from the Sun. It's our Solar system.

(Oort cloud. www.newscientist.com)