EARTH Science REVIEW

1. EARTH Science REVIEW

2. Our Solar System and its Planets The Solar System

3. Universe – Everything and Anything that has ever existed - billions of galaxies Galaxy – Ours is the Milky Way – Groups of Solar Systems bound together by gravity Solar System- consists of the Sun and those celestial objects bound to it by gravity The Universe – From Large to Small

4. The UNIVERSE and the BIG BANG Big Bang generally refers to the idea that the Universe has expanded from a primordial hot and dense initial condition at some finite time in the past (best available measurements in 2009 suggest that the initial conditions occurred around 13.3 to 13.9 billion years ago) and continues to expand to this day.

5. The Sun is the star at the center of the Solar System. The Sun has a diameter of about 1,392,000 kilometers (about 109 Earths) The mean distance of the Sun from the Earth is approximately 149.6 million kilometers (1 Astronomical Unit) The Sun

6. The moon is Earth's only natural satellite (orbiting body). • The moon is a cold, dry orb whose surface is studded with craters and strewn with rocks and dust. • The moon has no atmosphere. Recent lunar missions indicate that there might be some frozen ice at the poles. • The moon is about 238,900 miles (384,000 km) from Earth on average THE MOON

7. In Order From Sun Type of Planets • Mercury • Venus • Earth • Mars • Jupiter • Saturn • Uranus • Neptune • Terrestrials: Planets that are similar to Earth, with bodies largely composed of rock: Mercury, Venus, Earth and Mars. • Gas giants (Jovians): Planets with a composition largely made up of gaseous material and are significantly more massive than terrestrials: Jupiter, Saturn, Uranus, Neptune. Jupiter Planets In our Solar System

8. Concepts of Earth’s properties EARTH

9. EONTwo or more geological eras form an Eon, which is the largest division of geologic time, lasting many hundreds of millions of years. ERATwo or more geological periods comprise an era, which is hundreds of millions of years in duration. PERIODThe period is the basic unit of geological time in which a single type of rock system is formed, lasting tens of millions of years. EPOCHAn epoch is a division of a geologic period; it is the smallest division of geologic time, lasting several million years. AGEAn age is a unit of geological time which is distinguished by some feature (like an Ice Age). An age is shorter than epoch, usually lasting from a few million years to about a hundred million years. Reading Earth’s Timeline

10. Proterozoic Eon – First Fossils • Carboniferous Period – Evolution of Land Plants • Triassic Period – First “Dinosaurs” • Cretaceous Period – Extinction of “Dinosaurs” • Tertiary Period – Mammals and Birds Diversify • Quaternary Period – Evolution of Humans Earth’s Geologic TimeLine

11. THE EARTH'S ORBIT - On average, the Earth orbits, 93 million miles (149,600,000 km) from the Sun. This distance is defined as one Astronomical Unit (AU). The Earth is closest to the Sun (this is called perihelion) around January 3 each year (91.4 million miles = 147.1 million km); it is farthest away from the Sun (this is called aphelion) around July 4 each year (94.8 million miles = 152.6 million km). Earth AGE = 4.5 Billion Years Old

12. The Earth is the third planet from the Sun in our Solar System. It is the planet we evolved on and the only planet in our Solar System that is known to support life. • The Earth is about 7,926 miles (12,756 km) in diameter. The Earth is the fifth-largest planet in our Solar System (after Jupiter, Saturn, Uranus, and Neptune). INTRODUCTION TO THE EARTH

13. EARTH • MASS, DENSITY, AND ESCAPE VELOCITY • The Earth's mass is about 5.98 x 1024 kg. • The Earth has an average density of 5520 kg/m3 (water has a density of 1027 kg/m3). Earth is the densest planet in our Solar System. • To escape the Earth's gravitational pull, an object must reach a velocity of 24,840 miles per hour (11,180 m/sec). • LENGTH OF A DAY AND YEAR ON EARTH • Each day on Earth takes 23.93 hours (that is, it takes the Earth 23.93 hours to rotate around its axis once - this is a sidereal day). Each year on Earth takes 365.26 Earth days (that is, it takes the Earth 365.26 days to orbit the Sun once). • The Earth's rotation is slowing down very slightly over time, about one second every 10 years.

14. THE EARTH'S AXIS TILT AND THE SEASONS • The Earth's axis is tilted from perpendicular to the plane of the ecliptic by 23.45°. • This tilting is what gives us the four seasons of the year: Summer, Spring, Winter and Autumn. • Since the axis is tilted, different parts of the globe are oriented towards the Sun at different times of the year. • This affects the amount of sunlight each receives. EARTH

15. SolsticesThe solstices are days when the Sun reaches its farthest northern and southern declinations. The winter solstice occurs on December 21 or 22 and marks the beginning of winter (this is the shortest day of the year). • The summer solstice occurs on June 21 and marks the beginning of summer (this is the longest day of the year). • EquinoxesEquinoxes are days in which day and night are of equal duration. The two yearly equinoxes occur when the Sun crosses the celestial equator. • The vernal equinox occurs in late March (this is the beginning of spring in the Northern Hemisphere and the beginning of fall in the Southern Hemisphere); the autumnal equinox occurs in late September (this is the beginning of fall in the Northern Hemisphere and the beginning of spring in the Southern Hemisphere). Seasons

16. Layers of the Earth • The Earth is made of many different and distinct layers. The deeper layers are composed of heavier materials; they are hotter, denser and under much greater pressure than the outer layers. • Core: The Earth has a core that is about 2,100 miles in radius. The inner core may have a temperature up to about 13,000°F (which is hotter than the surface of the Sun. • The inner core (which has a radius of about 750 miles (1,228 km) is solid. • The outer core is in a liquid state and is about 1,400 miles (2,260 km) thick. • Mantle: The outer most layer of Earth which consist of the following • Lithosphere - contains the continents and the ocean (Including Crust– rigid and rocky • Asthenosphere - flowing layer of the upper mantle which holds plastic-like properties

17. Rock layers and types of rocks

18. Rock layers and types of rocks • Top Layers = Sedimentary - Newest • Bottom Layers = Igneous - Oldest • Mixed In = Metamorphic • Igneous Rocks – are crystalline solids which cool from magma which makes up most of the crust • EX. Granite, Pumice, Obsidian • Sedimentary Rocks - the rock which covers the igneous rock is a type of rock that is formed by sedimentation of material at the Earth's surface and within bodies of water. • EX. Sandstone & Limestone • Metamorphic Rocks - is the result of the transformation of an existing rock type • EX. Slate & Marble

19. Radioactive decay is the process by which an unstable atomic nucleus spontaneously loses energy by emitting ionizing particles and radiation becoming an Isotope. • 3Types – Alpha, Beta, and Gamma • Read by half life — the time taken for the activity of a given amount of a radioactive substance to decay to half of its initial value. • Many of Earth’s elements can become radioactive such as uranium, radon, plutonium, and polonium. Radioactivity and Decay

20. This theory explains the movement of the Earth's plates and also explains the cause of earthquakes, volcanoes, oceanic trenches, mountain range formation, and many other geologic phenomenon. Plate Tectonics

21. The drift or movement of the Earths plates across the Earth’s surface due to plate tectonics or the crust drifting on top of the mantle • The map of the Earth is always changing; not only are the underlying plates moving, but the plates change in size. Also, the sea level changes over time covering or exposing different amounts of crust. Continental Drift

22. Divergent Plate Movement: Seafloor Spreading Convergent Plate Movement: Volcanoes and Mountains are formed Lateral Slipping Plate Movement: Earthquakes TYPES OF PLATE MOVEMENT

23. The Pacific Ring of Fire (or sometimes just the Ring of Fire) is an area where large numbers of earthquakes and volcanic eruptions occur in the basin of a Pacific Ocean. • About 90% of the world's earthquakes and 80% of the world's largest earthquakes occur along the Ring of Fire. • The Ring of Fire is a direct result of plate tectonicsand the movement and collisions of crustal plates. Volcanoes - Ring of Fire A volcano is an opening, or rupture, in a planet's surface or crust, which allows hot magma, ash and gases to escape from below the surface.

24. Continents & Oceans • Continents • Africa • Antarctica • Asia • Australia • Europe • North America • South America • Major Oceans • Arctic • Atlantic • Indian • Pacific

25. Latitude and Longitude • Latitude (shown as a horizontal line) is the angular distance, in degrees, minutes, and seconds of a point north or south of the Equator. Lines of latitude are often referred to as parallels. • Longitude (shown as a vertical line) is the angular distance, in degrees, minutes, and seconds, of a point east or west of the Prime (Greenwich) Meridian. Lines of longitude are often referred to as meridians.

26. A perennial mass of ice which moves over land. • Glacier ice is the largest reservoir of fresh water on Earth, and is second only to oceans as the largest reservoir of total water. • Glaciers are indicators of climate and are important to world water resources and sea level variation. Glaciers

27. The Atmospheres layers and properties The Atmosphere

28. The Earth's atmosphere is a thin layer of gases that surrounds the Earth. • It composed of 78% nitrogen, 21% oxygen, 0.9% argon, 0.03% carbon dioxide, and trace amounts of other gases. • This thin gaseous layer insulates the Earth from extreme temperatures; it keeps heat inside the atmosphere and it also blocks the Earth from much of the Sun's incoming ultraviolet radiation. • The Earth's atmosphere is about 300 miles thick, but most of the atmosphere (about 80%) is within 10 miles of the surface of the Earth. There is no exact place where the atmosphere ends; it just gets thinner and thinner, until it merges with outer space. Earth’s Atmosphere

29. The atmosphere is divided into five layers. It is thickest near the surface and thins out with height until it eventually merges with space. 1) The troposphere is the first layer above the surface and contains half of the Earth's atmosphere. Weather occurs in this layer. 2) Many jet aircrafts fly in the stratosphere because it is very stable. Also, the ozone layer absorbs harmful rays from the Sun.3) Meteors or rock fragments burn up in the mesosphere.4) The thermosphere is a layer with auroras. It is also where the space shuttle orbits. 5) The atmosphere merges into space in the extremely thin exosphere. This is the upper limit of our atmosphere. Layers of the atmosphere

30. Air currents may be caused by differences in temperature, pressure, or impurity concentration. air moving (sometimes with considerable force) from an area of high pressure to an area of low pressure Also drive Ocean Currents and causes wind and airstreams Air currents

31. Types of Clouds

32. Low - Stratus clouds are uniform grayish clouds that often cover the entire sky. They resemble fog that does not reach the ground. • Middle - Altocumulus clouds are middle level clouds that are made of water droplets and appear as gray, puffy masses • High - Cirrus clouds are thin, wispy clouds blown by high winds into long streamers. They are considered "high clouds" forming above 6000 m (20,000 ft). Cirrus clouds usually move across the sky from west to east • Clouds With Vertical Development - Cumulus clouds - are puffy clouds that sometimes look like pieces of floating cotton. The base of each cloud is often flat and may be only 1000 m (330 ft) above the ground. The top of the cloud has rounded towers. When the top of the cumulus resembles the head of a cauliflower • Giant cumulonimbus - which is a thunderstorm cloud Types of Clouds

33. The Sun's heat provides energy to evaporate water from the Earth's surface (oceans, lakes, etc.). Plants also lose water to the air (this is called transpiration). The water vapor eventually condenses, forming tiny droplets in clouds. When the clouds meet cool air over land, precipitation (rain, sleet, or snow) is triggered, and water returns to the land (or sea). Some of the precipitation soaks into the ground. Some of the underground water is trapped between rock or clay layers; this is called groundwater. But most of the water flows downhill as runoff (above ground or underground). Water Cycle The Water Cycle, or hydrologic cycle, is the journey water takes as it circulates from the land to the sky and back again.

34. Weather – The state of the atmosphere at a given time and place, with respect to variables such as temperature, moisture, wind velocity, and barometric pressure. Climate - The meteorological conditions, including temperature, precipitation, and wind, that characteristically prevail in a particular region. Weather & Climate

35. Climate Change Climate change is a change in the statistical distribution of weather over periods of time that range from decades to millions of years. Human causes for change – Industrial Revolution, Aerosols, Burning of fossil fuels and biomass It can be a change in the average weather or a change in the distribution of weather events around an average (for example, greater or fewer extreme weather events). Climate change may be limited to a specific region, or may occur across the whole Earth. For more info for yourself go to:http://www.epa.gov/climatechange/

36. The greenhouse effect is an increase in the temperature of a planet as heat energy from sunlight is trapped by the gaseous atmosphere. • Excess carbon dioxide and water vapor increase this global warming effect. The Greenhouse Effect

37. THE END