Measuring+Earth

Measuring The Earth

//**﻿Earths Shape: **// Very close to being a perfect sphere Oblate Spheroid  Flattening at the polar regions  Slight Bulge at the equator

2.) Observations of Stars and 3.)Gravity is nearly equal strength at sea level all over the Earth's Surface Careful measurements show that there is a slightly greater gravitational pull at the poles 4) Spherical shadow cast during an eclipse of the moon 5.) Photographs from outer space
 * //﻿Evidence: //**
 * //﻿ //** 1.) Ships appear to sink past the horizon



//** Circumference of the Earth: ﻿ **// Eratosthenes Calculated the circumference of the earth about 2000 years ago //** How did he calculate it? **// //** 7.2 **// //** -= 5000 stadia **// //** 360- - **// //** X **// //** Circumfrence + 20000 staida **// //** His calculation was equivalent to 46,250 KM **// //**﻿What was Eratosthenes Precent Deviation? **// Its actual circumference is about 40,000 KM Eratosthenes Percent deviation was 16%

//**Total Surface Area: **// ﻿510 million square KM Water=361 million square KM Land= 149 million square KM

//**Earth's Layers: **//
 * <span style="color: #f55b75; font-family: 'Comic Sans MS',cursive; line-height: 0px; overflow-x: hidden; overflow-y: hidden;">Earth is made up of a series of spheres held together by gravity **
 * <span style="color: #f55b75; font-family: 'Comic Sans MS',cursive; line-height: 0px; overflow-x: hidden; overflow-y: hidden;">Arranged from lowest to highest density **

//**<span style="color: #84bdf6; font-family: 'Comic Sans MS',cursive; font-size: 130%;">Atmosphere: **// <span style="color: #84bdf6; font-family: 'Comic Sans MS',cursive;">The layer of gases that surrounds the earth above the surface (page 1 in the ESRT) <span style="color: #84bdf6; font-family: 'Comic Sans MS',cursive;">Composed manily of nitrogen and oxygen <span style="color: #84bdf6; font-family: 'Comic Sans MS',cursive;">Hundreds of KM thick <span style="color: #84bdf6; font-family: 'Comic Sans MS',cursive;">Farthest from the Earths center because it is the lease dense <span style="color: #84bdf6; font-family: 'Comic Sans MS',cursive;">Stratified to layers or zones each with its own distinct chareacterics <span style="color: #84bdf6; font-family: 'Comic Sans MS',cursive;"> -Troposphere, stratosphere, mesosphere, and thermosphere <span style="color: #84bdf6; font-family: 'Comic Sans MS',cursive;"> -The boundaries between layers are called pauses

Hydrosphere The layer pf liquid water that lies between the atmosphere and most of the lithosphere Covers 71% of the earth's surface average 3.8 KM in thickness Mostly hydrogen and oxygen

<span style="color: #000000; font-family: 'Comic Sans MS',cursive; font-size: 130%;">Lithosphere <span style="font-family: 'Comic Sans MS',cursive;">Layer of rock which forms soild outer shell <span style="font-family: 'Comic Sans MS',cursive;">approx. 100 KM thick <span style="font-family: 'Comic Sans MS',cursive;">Divided into the lithosphere plates.

<span style="color: #000000; font-family: 'Comic Sans MS',cursive; font-size: 130%;">Earths interior <span style="color: #000000; font-family: 'Comic Sans MS',cursive;">Region extending from the soild part of the earths supface to the earths center <span style="color: #000000; font-family: 'Comic Sans MS',cursive;">Increasing temp. and density with depth <span style="color: #ff8300; font-family: 'Comic Sans MS',cursive; line-height: 0px; overflow-x: hidden; overflow-y: hidden;">

//**<span style="color: #00ff54; font-family: 'Comic Sans MS',cursive; font-size: 140%;">Latitude and Longitude: **// <span style="color: #00ff54; font-family: 'Comic Sans MS',cursive; font-size: 120%;">﻿﻿Latitude: <span style="color: #00ff54; font-family: 'Comic Sans MS',cursive;">﻿The angular distance north or south of the equator <span style="color: #00ff54; font-family: 'Comic Sans MS',cursive;">Parallels of the Latitude consists of all the points have the same Latitude lying on a circle which is a parallel to the equator. <span style="color: #00ff54; font-family: 'Comic Sans MS',cursive;">Latitude increases to a maximum of 90° north and 90° south of the equator

<span style="color: #00ff54; font-family: 'Comic Sans MS',cursive;">WhenWriting a Location's Latiude you MUST include N or S <span style="color: #000000; font-family: arial,helvetica,sans-serif;"> Equator- marks the middle location on earths surface halfway between the geographic North and South Poles <span style="color: #000000; font-family: arial,helvetica,sans-serif;"> Tropics- Tropic of Cancer 23.5° N Tropic of Capricorn 23.5° S <span style="color: #000000; font-family: arial,helvetica,sans-serif;">Arctic Circle 66.5°N Antarctic Circle 66.5°S The altitude of Polaris equals the degree of latitude int he northern hemisphere <span style="color: #000000; font-family: arial,helvetica,sans-serif;">Zenith- The point directly overhead Altitude of polaris at the Equator=0° North pole= 90° //**__Longitude__**// Is an angular distance east or west of the prime meridian Meridian of longitude- A semi-circle on the earth's surface if the earths connecting the north and south poles Longitude increases east or west the prime meridian to 180° Prime meridian- The meridian of zero Longitude which passes through GreenWhich England. When Recording a locations longitude you must include Either "E" or "W" 15°=1 hour your time is ahead of Greenwich to the East, and behind Greenwich to the west The international date line is located 180° from the prime meridian Latitude and Longitude are measured in degrees and minutes 1 degree=60 minutes For example 42° 30"N, 75° 15"W