FANDOM


Earthh




OverviewEdit

Earth, the planet upon whitch we all live, is about 4.5 billion years old. It is the 5th largest of the eight know planets in our solar system, right after the Gas Giants, and is the 3rd planet from the sun, our local star. The atmosphere of Earth is composed of two major gases, nitrogen and oxygen. Although most of our atmosphere is made up of nitrogen, the oxygen is crucial to much of the life on earth. This is because animals, including humans, breathe it in and use it during cellular resperation to break down food and create energy. As most know, an earth day is about 24 hours long but there is more to that then is commonly known. Also and an Earth year is not exactly 365 days so we periodicly adjust our callenders to compensate for the in accuracy. Earth is tilted from our solar orbit and it is this tilt in the earth's axis that produces seasons. Also, there is a slight wobble to earth's rotation called precesion and this takes 26,000 years to go through a full cycle. Due to this wobble we don't always have the same north star the complete 26,00 years. Currently out north star is Polaris, but might be something different later on.


StructureEdit

Earth-cutaway.img assist custom

The Earth has many layers that make up its structure. The crust, 0 - 40 km' is where we live, water resides, and where our breathable air is found. Humanitty has devided the crust into sections. The dry over sealeval land is devided into 7 "contenents" and the water covered area, about Furthermore, 71% of the Earth, into the 4 ocean floors.The crust is relitivly as thin as the skin of an apple, the crust is thinner under the oceans than under the continents. The upper mantle, 40 - 2,700 Km, is the part of the structure that we see when volcanoes erupt or when plates are sperating from each other. The outer core, 2,890 - 5,150, is the first part of the crust and is main composed of molten metals such as, nickel and iron. The inner core, 5150 - 6378, is made of the same metals, but pressure is so great these metals cannot melt and solidified. The diameter of the Earth is 12,756.3 km and the mass is 5.927e24 kg. .

Surface FeaturesEdit

Biome1

As you see in photos, movies, or just walking out side the earth has a very wide spectrum of surface features. You'll see mountains, vallies, craters, forest, deserts, tundras, oceans, volcanoes, and so much more. As we look at our dry ground features we see that the earth is not truely round but has a surface that goes up and own like a rollercoaster. You'll see these gigantic bodies of oceans that over a majority of the earth's surface. beneath these oceans it is equally un even with canyons, dips, and underwater caves. The normanl lifeforms on earth breathe air that all life needs to survive.

AtmosphereEdit

Layers-of-the-atmosphere-29q693x



The atmospere of the earth is seperated into 4 parts: troposphere, stratosphere, mesospehere, and thermosphere. The troposphere starts at the Earth's surface and extends 8 to 14.5 kilometers away. This part of the atmosphere is the most dense out of all the layers. Almost all weather is in this region. The stratosphere starts just above the troposphere and extends to 50 kilometers high. This layer contains the Ozone Lyaer also. The mesosphere starts just above the stratosphere and extends to 85 kilometers high. The thermosphere starts just above the mesosphere and extends to 600 kilometers high. This layer of the atmospere is the hotest part because of the suns energy. Temperatures in this layer can go as high as 1,727 degrees Celsius. The atmosphere is a mixture of gasses. some of these gasses are used in animal breathing and photosynthesis. Dry air contains roughly (by volume) 78.09% nitrogen, 20.95%oxygen, 0.93% argon, 0.039% carbon dioxide, and small amounts of other gases. Air also contains a variable amount of water vapor, on average around 1%. While air content and atmospheric pressure varies at different layers, air suitable for the survival of terrestrial plants and terrestrial animals is currently only known to be found in Earth's troposphere and artificial atmospheres

SatellitesEdit

Moonphases

Earth-Moon systemEdit

One of the satellites of the Earth is her moon, Luna.Her average distance from Earth is 384,400km (250,000 miles). The Moon's Inclination to the ecliptic is about 5.145°. Unlike some other planets our home has only one moon. We believe it was formed about the same time as the Earth. About 4.5 to 4.6 billion years ago. Our moon is much smaller than Earth. Luna has 1% on Earth's mass. The moon has a diameter of 3475km at the equater, whitch is about one quarter of Eath's 12,756km (<8000miles) equatorial diameter and Average radius of 6,371,000m.

It takes the moon about a month to rotate the Earth. A lunar month also called a Synodic month, is the amount of time it takes for the moon to go around the earth once reletive to the sun and can be measured from full moon to full moon. this time period lasts about 29 days 12 hours 44 minutes. A Sidereal month is defined by the amount of time it takes for the moon to circle the Earth once reletive to a far away point in the sky besides the sun. A sidereal month is about 27 days 7 hours 43.1 minutes long.



Due to the moon rotating around the earth, the earth is also actually slowing down. In the distant future the Earth will become in sync with the moon, rotating about once a month. It will still orbit the sun, but the Earth itself will rotate slower. So as of now it takes 23.95 hours to rotate, but it will get longer and longer, till it comes in sync with the moon. We travel through 2 zones of high tides a day, because there are 2 tidal bulges that follow the Moon as the Earth rotates below it.

  1. Spring Tides-
  2. Neap Tides-


One other satellite is an asteroid called Cruithne. It rotates on one side of the sun and it crosses into our orbit. Since Cruithne doesn't physically cross our orbit, they won't hit the Earth. Cruthne orbits the sun but is in resonance with earth.



Earth-Sun systemEdit

Sun-and-earth


As Earth rotates, we orbit the sun from an average distance of 93,000,000miles. This rotation and orbit, directly or not, is what creates our days, years, and seasons.

We have devided each earth day into 24 hours and called it a Solar day. is the amount of time it takes for the earth to rotate once relative to the sun. So....... A Solar Day is the amount of time between any two consecutive occasions in which The Sun passes through any perticular maridiean.

On the other hand, one Sidereal day is the amount of time it takes for any point in space besides the sun, usually a far away star, to pass through any perticular maridian twice. about 23.9344696 hours

A Solar Year is the amount of time it takes for the earth to travel around the sun one time. For example from Summer Solstace to Summer solstace... one solar year is about 365.249days long.

Sidereal Year- The amount of time it takes the earth to orbit the sun with resprct to a distant point such as a far away star. 365.256363004 or 1.00003878 Solar Years or about 20 minuts longer than solar year so... 365 Days 6 Hours 9 Minuts 9.76 Seconds over time we have changed our Calendar as we made these discoveries... We started with 360days,then progressed to 365days, 365.25days, and finally our current 365.249days.

Also, there is a slight wobble to earth's rotation called precesion and this takes 26,000 years to go through a full cycle. Due to this wobble we don't always have the same north star the complete 26,00 years. Currently out north star is Polaris, but might be something different later on

The axis of earths spin is not perfectly perpendicular to the ecliptic created by its revolution around sol. In fact it is tilted about 23.5 off of it and Earth's Inclination to the plane of the Solar System is 23.5°.380px-AxialTiltObliquity

Solstices accur twice a year. They are what happens when the tilt of earths axis allows a hemesphere to be tilted tward the sun and the path of the sun crosses the highest and lowest Lateral point throughout the year. These points have very spacific names and locations. The Line of 23.5 degreese north latitude is called the tropinc of cancer. This is the farthest north that the sun passes. The day that the sun passes along the tropic of cancer, around June 21, is the longest day of the year for the northern hemisphere. This Day is refered to by northern hemespearers as the Summer solstace. This effect is mirrored over the equater 6 months later, around December 21, and is called the winter solstace. This is the shortest earth day for the Northern hemesphere but is the longest for the southern hemispere.

The change in the lenth of a day may seem like a strange idea but it is somethng we encounter every day. Take june 21, the longest day of our year, for example. On that day during our aproximated 24 hours we experiance about 14 hours of daylight and about 10 hours of night. Now that the sun has reached the tropic of cancer, its reletive maxima, it will appear to drop i untill it reaches its minima, the tropic of capricorn. As this happenes the lenth of each day will change. Begining after the summer solstace, every day we will experiance about 40 seconds more night and 40 seconds less daylight than the previous day. This will continue for about 6 months until the winter solstace, during witch we will see about 10 hours of daylight and about 14 hours of night. Begining the following day, this progression from summer to winter will be reversed at the same pace, and the cycle will begain again.400px-Hours of daylight vs latitude vs day of year

This change in day lenths shoud tell you something. From this one should see that this makes for the possibility of an equilibrum halfway between solstaces in which the day and night each take up exactly half of the day. This is exactly what happens, and we refer to these days as Equinoxes. It is caused when the sun is perpendicular to the direction of the tilt of earths axis. During an equinox, the sun is directly over the equater.

UT date and time of

equinoxes and solstices on the earth [1]

event

Northward

Northern

Southward

Southern

equinox

solstice

equinox

solstice

month

March

June

September

December

year

day

time

day

time

day

time

day

time

2010

20

17:32

21

11:28

23

3:09

21

23:38

2011

20

23:21

21

17:16

23

9:04

22

5:30

2012

20

5:14

20

23:09

22

14:49

21

11:12

2013

20

11:02

21

5:04

22

20:44

21

17:11

2014

20

16:57

21

10:51

23

2:29

21

23:03

2015

20

22:45

21

16:38

23

8:20

22

4:48

2016

20

4:30

20

22:34

22

14:21

21

10:44

2017

20

10:28

21

4:24

22

20:02

21

16:28

2018

20

16:15

21

10:07

23

1:54

21

22:23

2019

20

21:58

21

15:54

23

7:50

22

4:19

2020

20

3:50

20

21:44

22

13:31

21

10:02

Effects on seasons... The cycle of solstice, equinox, solstice, equinox is more than just a bunch of words that scientists throw around, they determin our seasons. We feel the affects of these seasons every day. Lets begin with the summer solstace... around june 21st

All of this data is given from the perspective of the northern hemesphere. In the sothern hemesphere the seasons are reletive opposites. Thus, one's summer is the others winter...

&nbsp Other Interactions

Solar Flairs and Storms cause the Aurora, affect Satellites, Power Grids, and Radio Communication

Precession of the Earth's Axis causes changes in seasons (Sahara was lush 5000 years ago)

In 4 billion years, the Sun will change and life will no longer be possible on Earth.




If looked down upon from above the Earth rotates counter clock-wise and also orbits the sun going counter clockwise. The orbit of the earth is not a circle, but an ellipse. The sun is not at the center of this ellipse, but is at one focus. So the earth does get closer and farther to sun, along with moving slower and faster. The earth has a tilt of 23.5 degress that gives the earth the ability to have seasons. As the earth rotates the sun it will have a part of it facing closer to sun at different points during the orbitof the sun. In this tilt as produces longer days and shorter nights and vice versa depending on which way the sun is leaning to.



Cruithne

OutlineEdit

I. Earth

A. Overview/Introduction
  
B. Structure
     1. Crust
     2. Mantel
     3. Outter Core
     4. Inner Core
  C. Surface Features
     1. Oceans/Seas
     2. Land
     3. General Lifeforms
  D. Atmosphere
     1. Troposphere
     2. Stratosphere
     3. Ozone
  E. Satelites
     1. Natural
     2. Man Made
  F. Motion/systems
     1. Orbit/ earth-sun system
     2. earth-moon systems




Earth Fiction


BibliographyEdit

Moore, Patrick. Exploring The Earth and Moon. New York, New York: W.H. Smith Publishers Inc, 1991.

Holt, Terry. The Universe Next Door. Canada: Collier Macmillan Canada, Inc.

http://seds.lpl.arizona.edu/nineplanets/nineplanets/earth.html

http://web.archive.org/web/20030801082655/http://www.space.com/scienceastronomy/101_earth_facts_030722-8.html

http://mars.sgi.com/worlds/CyberMarz/Earth/HTML/index.html

Ad blocker interference detected!


Wikia is a free-to-use site that makes money from advertising. We have a modified experience for viewers using ad blockers

Wikia is not accessible if you’ve made further modifications. Remove the custom ad blocker rule(s) and the page will load as expected.