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6th-grade science notes 

Parts of the Earth System

  • The earth system has four main spheres they are the atmosphere, the hydrosphere, the Geosphere, and the Biosphere

  • The sun can be considered part of the Earth System

  • Humans greatly affect the air, water, land, and life on Earth through the decisions they make each day

  • Atmosphere: outermost layer is a mixture of gases(mostly nitrogen and oxygen) It contains the Earth’s weather and is the foundation for different climates around the world.

  • Geosphere: Nearly all the earth’s mass is found in the earth’s solid rocks and metals. A metal core a solid middle layer and a rocky outer layer are the three main parts of the Geosphere.

  • Hydrosphere: The Hydrosphere contains all of the Earth’s water

  • Biosphere: All parts of the earth that contain living organisms make up the biosphere

Energy and Energy Resources

  • Potential energy is not in use and is available to do work

  • Kinetic energy is in use

  • Chemical energy in fossil fuels is potential energy until it is released.

  • Solar Energy from the ancient past is stored in fossil fuels, such as coal, petroleum, and natural gas.

  • Fossil fuels are rich in the elements carbon and hydrogen. It is nonrenewable.

  • Nuclear power is also considered a source of nonrenewable energy.

  • Solar, wind, water, biofuels, and geothermal energy are all considered renewable

  • Secondary sources of energy such as electricity, are used to store, move and deliver energy easily in a usable form

  • Hydrogen is also called an energy carrier.

  • Thermal and radiant energy can be converted into mechanical energy, chemical energy, and electrical energy and back again.

  • Hydrogen is not an energy source

  • Mechanical energy is the total amount of potential and kinetic energy combined in an object

  • Gravitational potential energy is due to the height of an object on the ground

  • Elastic potential energy is the mechanical energy due to the object’s shape.

  • Electrical energy is the energy from electric charges

  • Nuclear energy is the potential energy stored in an atom’s nucleus

  • Electromagnetic Energy: in the form of energy that travels through space in waves. Light waves are a type of electromagnetic energy

  • Thermal energy is the total kinetic and potential energy of the particles within an object that is at rest. The warmer the object is the faster the particles move and the more kinetic energy it has.

  • Chemical energy: is potential energy stored in chemical bonds

  • Energy Transformation: is the change of energy from one form to another.

Non-Renewable Energy Sources

  • Fuel is a substance that provides energy such as heat light motion or electricity.

  • The sun has played a central role in the formation of many of the fuels we use as energy sources. Most of the energy we use today comes from organisms that lived a long time ago.

  • Fossil Fuels are the remains of dead organisms

  • The three major fossil fuels are coal, oil, and natural gas

Fossil fuels are made of hydrocarbons. Hydrocarbons are chemical compounds that contain carbon and hydrogen atoms.

  • Coal is the most plentiful fossil fuel in the United States

  • Oil – Oil is a thick, black, liquid fossil fuel.

    Petroleum/oil accounts for more than one-third of the energy produced in the whole world.

    ---When oil is first pumped out of the ground, it is called crude oil.

---Natural gas- Natural gas is a mixture of methane and other gases.

---Since fossil fuels take an EXCEPTIONALLY long time to form, they are considered nonrenewable resources. Eventually, they will run out if they are used faster than they are formed, and currently, we as a whole are using more fossil fuels than are being formed.

---Nuclear Power- Like solar, water, and wind, nuclear power also does not produce air pollution since no fuel is burned.

---This process can be dangerous and even cause explosions if too much energy is released. Additionally, wastes generated by nuclear plants can be dangerous if disposed of improperly.

---Nuclear will be classified as a non-renewable

Renewable Sources of Energy

Renewable energy sources are sources that can be renewed faster than they can be used. Some sources of renewable energy include sunlight, water, wind, biomass fuels, geothermal energy, and hydrogen power. Scientists are working hard today to put these energy sources to work.

Solar Energy – Solar energy is energy from the sun.

Passive Solar Heating – in passive solar system sunlight converts into heat or thermal energy

Hydroelectric power- is electricity produced by flowing water.

Wind Power- Wind energy is also an indirect form of solar power.

Biomass Fuels – Biomass fuels are made from living things. Wood is probably one of the biggest biomass fuels used today! Other biomass fuels include leaves, food wastes (leftover food burned), and manure (any type of feces).

Adding alcohol to gasoline forms gasohol.

Geothermal Energy- The intense heat from Earth’s interior that warms magma underneath the ground is called geothermal energy.

How can we ensure that there will be enough energy for the future?

one way to preserve our current energy resources is to increase the efficiency

Energy Efficiency is the percentage of energy that is used to perform work.

Energy Conservation is the act of trying to reduce energy usage.

One way to increase energy efficiency is to use insulation.

Solar Energy and natural processes within the atmosphere and on Earth’s surface.

The Earth receives only a very small portion of the sun’s energy, yet this energy is responsible for powering the motion of the atmosphere, the oceans, and many processes at the Earth’s surface. About one-half of the energy striking Earth is absorbed by Earth’s surface. About one-third of the sun’s incoming energy is reflected out to space.

Excess carbon dioxide and other gases may disrupt this balance, creating a greenhouse effect.

Remember, the Earth’s surface is heated unequally.

Water and its’ important properties & Characteristics

Among water’s unique properties is that one side of each water molecule is slightly negative and the other is slightly positive (thus it is classified as a polar molecule).

Due to water’s polar nature, a large number of substances will “dissolve” in water. For this reason, water is often called the universal solvent.

Water is the only compound that commonly exists in all three states (solid, liquid, gas) on Earth. The unique properties of water are a major factor in the ability of our planet to sustain life.

Water (rain, ice, snow) has shaped our environment by physically and chemically weathering

Water can absorb thermal energy without showing relatively large temperature changes. Therefore, it is said to have a very high specific heat.

Most of Earth’s water is salt water in the oceans (97 percent). Non-frozen, freshwater makes up less than 1 percent of the water on Earth.

Due to water’s importance in power generation, agriculture, and human health, it is important to conserve water resources

Water Cycle: In the water cycle, water vapor enters the atmosphere by evaporation from the oceans and vapor enters the atmosphere by evaporation from the oceans and other bodies of water and leaves by condensation.

The Earth’s Atmosphere

Air is a mixture of gaseous elements and compounds. These include nitrogen, oxygen, water, argon, and carbon dioxide. Nitrogen makes up the largest proportion of air. It makes up a little more than ¾ of the air we breathe.

Oxygen: This is the second most abundant gas in the atmosphere and makes up about 21% of the volume.

Carbon Dioxide: Makes up much less than 1% of the atmosphere but is essential to life. Plants must have carbon dioxide to produce food.

The atmosphere is made up of layers (troposphere, stratosphere, mesosphere, and thermosphere) that have distinct characteristics. Temperature decreases as altitude increases in the lowest layer of the atmosphere. Most of the air that makes up the atmosphere is found in the troposphere (the lowest layer). Virtually all weather takes place in the troposphere.

Troposphere – the layer of the atmosphere in which Earth’s weather occurs.

Stratosphere: The stratosphere extends from the top of the troposphere to about 50 km above the Earth’s surface. It is the second layer of the atmosphere and contains the ozone layer.

The mesosphere: Above the stratosphere, a drop in temperature marks the beginning of this layer. Meso-, meaning middle, is the middle layer of the atmosphere. The mesosphere is the layer of the atmosphere that protects Earth’s surface from being hit the most by meteoroids.

Thermosphere: This is the outermost layer of the Earth’s atmosphere that extends from about 80 km above the Earth’s surface with no outward limit going into space.

Wind Speed- Wind speed can be measured with an anemometer. It has 3 or 4 cups mounted at the ends of spokes that spin on an axle. The force of the wind against the cups turns the axle.

---Wind chill factor: Wind chill factor measures the increased cooling that wind can cause in the atmosphere.

Local Winds: the unequal heating of the Earth’s surface within a small area causes local wind. Two types of local winds are sea breezes and land breezes.

Global Winds are winds that blow steadily from specific directions over long distances.

Coriolis effect- The Earth’s rotation makes winds curve called the Coriolis Effect. Weather:

The Atmosphere: Weather is the condition of Earth’s atmosphere at a particular time and place. Earth’s atmosphere is the envelope of gases that surrounds the planet.

Water vapor- Water in the form of a gas.

The amounts of thermal energy and water vapor in the air and the pressure of the air largely determine what the weather conditions are. Clouds are important indicators of atmospheric conditions. Clouds are found at various levels within the troposphere. Three major types of clouds are cumulus, stratus, and cirrus.

Clouds: How do clouds form? Clouds form when water vapor in the air condenses to form liquid water or ice crystals.

Dew point: The temperature at which condensation begins and forms droplets. The three main types of clouds:

Cirrus – They look wispy, and feathery, and form at high altitudes. Made of ice crystals and indicate fair weather.

Cumulus- Look like cotton/ puffy clouds and usually indicate fair weather

Stratus Clouds- usually form in flat layers and typically cover all or most of the sky and are dull, and gray. They produce drizzle, rain, and/or snow.

Precipitation – is any form of water that falls back to the surface.

A barometer is an instrument that is used to measure air pressure.

Altitude- or elevation is the distance above sea level. Air pressure decreases as altitude increases. As air pressure decreases, so does density.

Humidity is the measure of the amount of water vapor in the air.

A hygrometer is an instrument to measure the amount of moisture in the air or humidity. Maintaining good air quality is a crucial goal for modern society, and it is everyone’s responsibility to work toward it.

*A cold front is defined as the leading edge of a cooler mass of air, replacing at ground level a warmer mass of air, which lies within a fairly sharp surface trough of low pressure.

*A warm front is a density discontinuity located at the leading edge of a homogeneous warm air mass and is typically located on the equator-facing edge of an isotherm gradient.

  • An Occluded front is formed during the process of cyclogenesis when a cold front overtakes a warm front.

  • *A Stationary front is a pair of air masses, neither of which is strong enough to replace the other. On a weather map, this is shown by an inter-playing series of blue spikes pointing in one direction and red domes pointing in the other.

Greenhouse gases/ Greenhouse effect- Many human activities are increasing the level of greenhouse gases in the atmosphere and producing changes in climate worldwide. This increase is causing global temperatures to rise.

Fossil fuels – are energy-rich substances formed from the remains of organisms.

Global Warming- The gradual increase in the temperature of Earth’s atmosphere.

Water Sheds

An ecosystem is made up of the biotic (living) community and the abiotic (nonliving) factors that affect it. The health of an ecosystem is directly related to water quality. Abiotic factors determine ecosystem type and its distribution of plants and animals as well as the usage of land by people.

A watershed is a land that water flows across or through on its way to a stream, lake, wetland, or other body of water.

**The three major regional watershed systems in Virginia lead to the Chesapeake Bay, the North Carolina Sounds, and the Gulf of Mexico.

Wetlands form the transition zone between dry land and bodies of water such as rivers, lakes, or bays.

Estuaries perform important functions, such as providing habitat for many organisms and serving as nurseries for their young.

The Chesapeake Bay is an estuary where fresh and saltwater meet and are mixed by tides. It is the largest estuary in the contiguous United States and one of the most productive.

Virginia Watersheds: Many rivers crisscross Virginia leaving a wealth of watersheds. Most of the water in these watersheds flows into the Chesapeake Bay and then into the Atlantic Ocean. Other watersheds in Virginia flow into either the North Carolina sounds (The Roanoke River dumps into the North Carolina Sounds) or the Gulf of Mexico (Radford and Christiansburg will dump into the Gulf of Mexico). The James River watershed is the largest of Virginia’s watersheds and dumps into the Chesapeake Bay.

Divides: A divide is a ridge of land that separates one watershed from another.

The solar system consists of the Sun, Moon, Earth, other planets and their moons, meteors, asteroids, and comets.

The moon is Earth’s only natural satellite

Meteors: A streak of light produced when a small object burns up as it enters the Earth’s atmosphere. These look like, “shooting stars.”

Comets: A comet is a cold mixture of dust and ice that gives up a long trail of light as it approaches the sun.

(It is the fourth phase of matter—Plasma). Planets: A planet is an object that orbits the sun, is large enough to have become rounded by its gravity, and has cleared the area of its orbit. There are eight planets in our solar system. Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto. The distance between planets and the sizes of the planets vary greatly. The outer, “gas” planets are very large, and the four inner planets are comparatively small and rocky. **The asteroid belt is located between the inner rocky planets and the outer gas planets (between Mars and Jupiter).

Gravity is a force that keeps the planets in motion around the sun. Gravity acts everywhere in the universe.

The Earth moves by Rotation and Revolution. The Earth spins on an axis. This spinning of the Earth on its axis is called rotation. The earth’s rotation causes day

The asteroid belt is in between Mars and Jupiter and is represented by all the little dots in the picture. Dwarf planets here in our solar system. and night.

As Earth rotates, different sides of Earth face toward or away from the sun, thus causing day and night, respectively. In addition to rotating, the Earth travels around the sun (orbits the Sun).

Revolution is the movement of one object around another, so the Earth stays in revolution around the Sun (called an orbit). Seasons are caused by a combination of the tilt of the Earth on its axis, the curvature of the Earth’s surface (Revolution), and, thus, the angle at which sunlight strikes the surface of Earth during its annual revolution around the sun.

1.) New Moon

2.) Waxing crescent

3.) First Quarter

4.)Waxing gibbous

5.) Full moon

6.) Waning gibbous

7.) Third Quarter

8.) Waning crescent

Tides are the result of the gravitational pull of the moon and sun on the surface waters of Earth.

Ptolemy was an astronomer and mathematician. He believed that the Earth was the center of the Universe.

Aristotle was sometimes called the grandfather of science. He studied under the great philosopher Plato and later started his school. He, too, believed in a geocentric Universe and that the planets and stars were perfect spheres though Earth itself was not. He further thought that the movements of the planets and stars must be circular since they were perfect and if the motions were circular, then they could go on forever.

Copernicus came up with a radical way of looking at the Universe. His heliocentric system put the Sun (helio) at the center of our system.

Galileo devised a telescope that could enlarge objects up to 20 times. He was able to use this telescope to prove the truth of the Copernican system of heliocentrism (the sun is the center of our universe and the planets move around it).

Phases are caused by the motions of the moon around the Earth.

A vacuum is a place that is empty of all matter.

Standard Policy decisions related to the environment

Conservation of resources and environmental protection begins with individual acts of stewardship.

Eutrophication – the process of nutrients building up in a lake over time.

A wetland is a land area that is covered with a shallow layer of water during some or all the year.

Most water pollution is the result of human activities.

MW

6th-grade science notes 

Parts of the Earth System

  • The earth system has four main spheres they are the atmosphere, the hydrosphere, the Geosphere, and the Biosphere

  • The sun can be considered part of the Earth System

  • Humans greatly affect the air, water, land, and life on Earth through the decisions they make each day

  • Atmosphere: outermost layer is a mixture of gases(mostly nitrogen and oxygen) It contains the Earth’s weather and is the foundation for different climates around the world.

  • Geosphere: Nearly all the earth’s mass is found in the earth’s solid rocks and metals. A metal core a solid middle layer and a rocky outer layer are the three main parts of the Geosphere.

  • Hydrosphere: The Hydrosphere contains all of the Earth’s water

  • Biosphere: All parts of the earth that contain living organisms make up the biosphere

Energy and Energy Resources

  • Potential energy is not in use and is available to do work

  • Kinetic energy is in use

  • Chemical energy in fossil fuels is potential energy until it is released.

  • Solar Energy from the ancient past is stored in fossil fuels, such as coal, petroleum, and natural gas.

  • Fossil fuels are rich in the elements carbon and hydrogen. It is nonrenewable.

  • Nuclear power is also considered a source of nonrenewable energy.

  • Solar, wind, water, biofuels, and geothermal energy are all considered renewable

  • Secondary sources of energy such as electricity, are used to store, move and deliver energy easily in a usable form

  • Hydrogen is also called an energy carrier.

  • Thermal and radiant energy can be converted into mechanical energy, chemical energy, and electrical energy and back again.

  • Hydrogen is not an energy source

  • Mechanical energy is the total amount of potential and kinetic energy combined in an object

  • Gravitational potential energy is due to the height of an object on the ground

  • Elastic potential energy is the mechanical energy due to the object’s shape.

  • Electrical energy is the energy from electric charges

  • Nuclear energy is the potential energy stored in an atom’s nucleus

  • Electromagnetic Energy: in the form of energy that travels through space in waves. Light waves are a type of electromagnetic energy

  • Thermal energy is the total kinetic and potential energy of the particles within an object that is at rest. The warmer the object is the faster the particles move and the more kinetic energy it has.

  • Chemical energy: is potential energy stored in chemical bonds

  • Energy Transformation: is the change of energy from one form to another.

Non-Renewable Energy Sources

  • Fuel is a substance that provides energy such as heat light motion or electricity.

  • The sun has played a central role in the formation of many of the fuels we use as energy sources. Most of the energy we use today comes from organisms that lived a long time ago.

  • Fossil Fuels are the remains of dead organisms

  • The three major fossil fuels are coal, oil, and natural gas

Fossil fuels are made of hydrocarbons. Hydrocarbons are chemical compounds that contain carbon and hydrogen atoms.

  • Coal is the most plentiful fossil fuel in the United States

  • Oil – Oil is a thick, black, liquid fossil fuel.

    Petroleum/oil accounts for more than one-third of the energy produced in the whole world.

    ---When oil is first pumped out of the ground, it is called crude oil.

---Natural gas- Natural gas is a mixture of methane and other gases.

---Since fossil fuels take an EXCEPTIONALLY long time to form, they are considered nonrenewable resources. Eventually, they will run out if they are used faster than they are formed, and currently, we as a whole are using more fossil fuels than are being formed.

---Nuclear Power- Like solar, water, and wind, nuclear power also does not produce air pollution since no fuel is burned.

---This process can be dangerous and even cause explosions if too much energy is released. Additionally, wastes generated by nuclear plants can be dangerous if disposed of improperly.

---Nuclear will be classified as a non-renewable

Renewable Sources of Energy

Renewable energy sources are sources that can be renewed faster than they can be used. Some sources of renewable energy include sunlight, water, wind, biomass fuels, geothermal energy, and hydrogen power. Scientists are working hard today to put these energy sources to work.

Solar Energy – Solar energy is energy from the sun.

Passive Solar Heating – in passive solar system sunlight converts into heat or thermal energy

Hydroelectric power- is electricity produced by flowing water.

Wind Power- Wind energy is also an indirect form of solar power.

Biomass Fuels – Biomass fuels are made from living things. Wood is probably one of the biggest biomass fuels used today! Other biomass fuels include leaves, food wastes (leftover food burned), and manure (any type of feces).

Adding alcohol to gasoline forms gasohol.

Geothermal Energy- The intense heat from Earth’s interior that warms magma underneath the ground is called geothermal energy.

How can we ensure that there will be enough energy for the future?

one way to preserve our current energy resources is to increase the efficiency

Energy Efficiency is the percentage of energy that is used to perform work.

Energy Conservation is the act of trying to reduce energy usage.

One way to increase energy efficiency is to use insulation.

Solar Energy and natural processes within the atmosphere and on Earth’s surface.

The Earth receives only a very small portion of the sun’s energy, yet this energy is responsible for powering the motion of the atmosphere, the oceans, and many processes at the Earth’s surface. About one-half of the energy striking Earth is absorbed by Earth’s surface. About one-third of the sun’s incoming energy is reflected out to space.

Excess carbon dioxide and other gases may disrupt this balance, creating a greenhouse effect.

Remember, the Earth’s surface is heated unequally.

Water and its’ important properties & Characteristics

Among water’s unique properties is that one side of each water molecule is slightly negative and the other is slightly positive (thus it is classified as a polar molecule).

Due to water’s polar nature, a large number of substances will “dissolve” in water. For this reason, water is often called the universal solvent.

Water is the only compound that commonly exists in all three states (solid, liquid, gas) on Earth. The unique properties of water are a major factor in the ability of our planet to sustain life.

Water (rain, ice, snow) has shaped our environment by physically and chemically weathering

Water can absorb thermal energy without showing relatively large temperature changes. Therefore, it is said to have a very high specific heat.

Most of Earth’s water is salt water in the oceans (97 percent). Non-frozen, freshwater makes up less than 1 percent of the water on Earth.

Due to water’s importance in power generation, agriculture, and human health, it is important to conserve water resources

Water Cycle: In the water cycle, water vapor enters the atmosphere by evaporation from the oceans and vapor enters the atmosphere by evaporation from the oceans and other bodies of water and leaves by condensation.

The Earth’s Atmosphere

Air is a mixture of gaseous elements and compounds. These include nitrogen, oxygen, water, argon, and carbon dioxide. Nitrogen makes up the largest proportion of air. It makes up a little more than ¾ of the air we breathe.

Oxygen: This is the second most abundant gas in the atmosphere and makes up about 21% of the volume.

Carbon Dioxide: Makes up much less than 1% of the atmosphere but is essential to life. Plants must have carbon dioxide to produce food.

The atmosphere is made up of layers (troposphere, stratosphere, mesosphere, and thermosphere) that have distinct characteristics. Temperature decreases as altitude increases in the lowest layer of the atmosphere. Most of the air that makes up the atmosphere is found in the troposphere (the lowest layer). Virtually all weather takes place in the troposphere.

Troposphere – the layer of the atmosphere in which Earth’s weather occurs.

Stratosphere: The stratosphere extends from the top of the troposphere to about 50 km above the Earth’s surface. It is the second layer of the atmosphere and contains the ozone layer.

The mesosphere: Above the stratosphere, a drop in temperature marks the beginning of this layer. Meso-, meaning middle, is the middle layer of the atmosphere. The mesosphere is the layer of the atmosphere that protects Earth’s surface from being hit the most by meteoroids.

Thermosphere: This is the outermost layer of the Earth’s atmosphere that extends from about 80 km above the Earth’s surface with no outward limit going into space.

Wind Speed- Wind speed can be measured with an anemometer. It has 3 or 4 cups mounted at the ends of spokes that spin on an axle. The force of the wind against the cups turns the axle.

---Wind chill factor: Wind chill factor measures the increased cooling that wind can cause in the atmosphere.

Local Winds: the unequal heating of the Earth’s surface within a small area causes local wind. Two types of local winds are sea breezes and land breezes.

Global Winds are winds that blow steadily from specific directions over long distances.

Coriolis effect- The Earth’s rotation makes winds curve called the Coriolis Effect. Weather:

The Atmosphere: Weather is the condition of Earth’s atmosphere at a particular time and place. Earth’s atmosphere is the envelope of gases that surrounds the planet.

Water vapor- Water in the form of a gas.

The amounts of thermal energy and water vapor in the air and the pressure of the air largely determine what the weather conditions are. Clouds are important indicators of atmospheric conditions. Clouds are found at various levels within the troposphere. Three major types of clouds are cumulus, stratus, and cirrus.

Clouds: How do clouds form? Clouds form when water vapor in the air condenses to form liquid water or ice crystals.

Dew point: The temperature at which condensation begins and forms droplets. The three main types of clouds:

Cirrus – They look wispy, and feathery, and form at high altitudes. Made of ice crystals and indicate fair weather.

Cumulus- Look like cotton/ puffy clouds and usually indicate fair weather

Stratus Clouds- usually form in flat layers and typically cover all or most of the sky and are dull, and gray. They produce drizzle, rain, and/or snow.

Precipitation – is any form of water that falls back to the surface.

A barometer is an instrument that is used to measure air pressure.

Altitude- or elevation is the distance above sea level. Air pressure decreases as altitude increases. As air pressure decreases, so does density.

Humidity is the measure of the amount of water vapor in the air.

A hygrometer is an instrument to measure the amount of moisture in the air or humidity. Maintaining good air quality is a crucial goal for modern society, and it is everyone’s responsibility to work toward it.

*A cold front is defined as the leading edge of a cooler mass of air, replacing at ground level a warmer mass of air, which lies within a fairly sharp surface trough of low pressure.

*A warm front is a density discontinuity located at the leading edge of a homogeneous warm air mass and is typically located on the equator-facing edge of an isotherm gradient.

  • An Occluded front is formed during the process of cyclogenesis when a cold front overtakes a warm front.

  • *A Stationary front is a pair of air masses, neither of which is strong enough to replace the other. On a weather map, this is shown by an inter-playing series of blue spikes pointing in one direction and red domes pointing in the other.

Greenhouse gases/ Greenhouse effect- Many human activities are increasing the level of greenhouse gases in the atmosphere and producing changes in climate worldwide. This increase is causing global temperatures to rise.

Fossil fuels – are energy-rich substances formed from the remains of organisms.

Global Warming- The gradual increase in the temperature of Earth’s atmosphere.

Water Sheds

An ecosystem is made up of the biotic (living) community and the abiotic (nonliving) factors that affect it. The health of an ecosystem is directly related to water quality. Abiotic factors determine ecosystem type and its distribution of plants and animals as well as the usage of land by people.

A watershed is a land that water flows across or through on its way to a stream, lake, wetland, or other body of water.

**The three major regional watershed systems in Virginia lead to the Chesapeake Bay, the North Carolina Sounds, and the Gulf of Mexico.

Wetlands form the transition zone between dry land and bodies of water such as rivers, lakes, or bays.

Estuaries perform important functions, such as providing habitat for many organisms and serving as nurseries for their young.

The Chesapeake Bay is an estuary where fresh and saltwater meet and are mixed by tides. It is the largest estuary in the contiguous United States and one of the most productive.

Virginia Watersheds: Many rivers crisscross Virginia leaving a wealth of watersheds. Most of the water in these watersheds flows into the Chesapeake Bay and then into the Atlantic Ocean. Other watersheds in Virginia flow into either the North Carolina sounds (The Roanoke River dumps into the North Carolina Sounds) or the Gulf of Mexico (Radford and Christiansburg will dump into the Gulf of Mexico). The James River watershed is the largest of Virginia’s watersheds and dumps into the Chesapeake Bay.

Divides: A divide is a ridge of land that separates one watershed from another.

The solar system consists of the Sun, Moon, Earth, other planets and their moons, meteors, asteroids, and comets.

The moon is Earth’s only natural satellite

Meteors: A streak of light produced when a small object burns up as it enters the Earth’s atmosphere. These look like, “shooting stars.”

Comets: A comet is a cold mixture of dust and ice that gives up a long trail of light as it approaches the sun.

(It is the fourth phase of matter—Plasma). Planets: A planet is an object that orbits the sun, is large enough to have become rounded by its gravity, and has cleared the area of its orbit. There are eight planets in our solar system. Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto. The distance between planets and the sizes of the planets vary greatly. The outer, “gas” planets are very large, and the four inner planets are comparatively small and rocky. **The asteroid belt is located between the inner rocky planets and the outer gas planets (between Mars and Jupiter).

Gravity is a force that keeps the planets in motion around the sun. Gravity acts everywhere in the universe.

The Earth moves by Rotation and Revolution. The Earth spins on an axis. This spinning of the Earth on its axis is called rotation. The earth’s rotation causes day

The asteroid belt is in between Mars and Jupiter and is represented by all the little dots in the picture. Dwarf planets here in our solar system. and night.

As Earth rotates, different sides of Earth face toward or away from the sun, thus causing day and night, respectively. In addition to rotating, the Earth travels around the sun (orbits the Sun).

Revolution is the movement of one object around another, so the Earth stays in revolution around the Sun (called an orbit). Seasons are caused by a combination of the tilt of the Earth on its axis, the curvature of the Earth’s surface (Revolution), and, thus, the angle at which sunlight strikes the surface of Earth during its annual revolution around the sun.

1.) New Moon

2.) Waxing crescent

3.) First Quarter

4.)Waxing gibbous

5.) Full moon

6.) Waning gibbous

7.) Third Quarter

8.) Waning crescent

Tides are the result of the gravitational pull of the moon and sun on the surface waters of Earth.

Ptolemy was an astronomer and mathematician. He believed that the Earth was the center of the Universe.

Aristotle was sometimes called the grandfather of science. He studied under the great philosopher Plato and later started his school. He, too, believed in a geocentric Universe and that the planets and stars were perfect spheres though Earth itself was not. He further thought that the movements of the planets and stars must be circular since they were perfect and if the motions were circular, then they could go on forever.

Copernicus came up with a radical way of looking at the Universe. His heliocentric system put the Sun (helio) at the center of our system.

Galileo devised a telescope that could enlarge objects up to 20 times. He was able to use this telescope to prove the truth of the Copernican system of heliocentrism (the sun is the center of our universe and the planets move around it).

Phases are caused by the motions of the moon around the Earth.

A vacuum is a place that is empty of all matter.

Standard Policy decisions related to the environment

Conservation of resources and environmental protection begins with individual acts of stewardship.

Eutrophication – the process of nutrients building up in a lake over time.

A wetland is a land area that is covered with a shallow layer of water during some or all the year.

Most water pollution is the result of human activities.