miércoles, 29 de septiembre de 2010

Earth´s water supply

                                                                            Vocabulary#16
desalination: getting fresh water from seawater.

water cycle: the continious movement of water between Earth´s surface and the air, changing from liquid to gas to liquid.
ground water: water that seeps into the ground into spaces between bits of rock and soil

Earth´s Atmosphere

                                                                         Vocabulary#13
renewable resource: a resource that can be replaced in a short period of time.

ozone layer: a layer of ozone gas in the atmosphere that screens out much of the Sun´s UV rays.

fossil fuel: a fuel formed from the decay of acient forms of life.

smog: a mixture of smoke and fog.

acid rain: moisture that falls to Earth after being mixed with wastes from burned fossils fuels

Earth´s Rock and Soil

                                                                            Vocabulary#12
rock: a naturally formed solid in the crust,made up of one or more minerals.

igneous rock: a rock formed when melted rock materials cools and hardens.

sedimentary rock: a rock made of bits of matter joined together.

fossil: any remains or imprint of living things of the past.

metamorphic rock: a rock formed under heat and pressure from another kind of rock.

humus: decayed plant or animal material in soil.

pollution: adding any harmful substances to Earth´s land,water,or air.

Rock cycle: rocks changing from one form into another in a never-ending series of processes.

Minerals of Earth´s Crust

                                                                Vocabulary#11
mineral: a solid material of Earth´s crust with a definite composition.

luster:the way light bounces off a mineral´s surface.

streak: the color of the powder left when a mineral is rubbed against a hard ,rough surface.

hardness: how well a mneral resist´s scratching.

cleavage: the tendency of a mineral to break along flat surfaces.

ore :a mineral containig a useful subtance.

gem: a mineralvalued for being rare and beatiful

nonrewable resource:a resouce that cannot be replaced ithing a short period of time or at all.

Earth´s changing Crust

                                                                             vocabulary#10
fault: a crack in the crust, whose sides show evidence of motion.

geologist: a scientist who studies earth.

magma: hot,molten rock deep below earth´s surface.

lava: magma that reaches Earth´s surface.

weathearing: the breking down of rocks into smaller pieces.

erosion: the picking up and carrying away of pieces of rock.

deposition: the dropping off of bits of eroded rock.

meteorite: a chunk of rock from space that strikes a surface(such as Earth or the Moon).

Earths and its neighbors

                                                                           Vocabulary#8
solar system: the sun and the objects that are traveling around it.

planet: any of the nine large bodies that travel around the sun and shiny by  reflecting its light.

gravity: a force of attraction,or pull,between any objectsand any other objects around it.

inertia: the tendency of a moving object to keep moving in a strigh line.

lithosphere:the hard,outer layer of earth,about 100 kilometers thick.

crust: the rocky surface that makes up the top of the lithosphere

resource: any material that helps support life on Earth.

hydrosphere: Earth´s water.

Chemical changes

                                                                              Vocabulary#7
physical changes: a change in size,shape,or state,without forming a new substance.

chemical change: a change in matter that produces a new substances a new substance with different properties from the original.
chemical reaction: a chemical change of original substances into one or more new substances.

reactant: one of the original substances before a chemical reaction takes place.

product: one of the new substances produced when a chemical reaction takes place.

What matter is made Of

                                                                              Vocabulary#6
Element: a basic building block of matter ;a pure substance that cannot be broken down into anything simpler.
compound: a chemical combination of two or more elements into a single substance.

atom: the smallest unit of an element that still has the properties of the element.

proton: a particle with a positive charge in the nucleus of an atom.

neutron: an uncharged particle in the nucleus of an atom.

electron: a particle with a negative charge moving around the nucleus of an atom.

nucleus: the dense center part of an atom.

molecule: a group of more than one atom joined together that acts like a single particle.

What matter Is

                                                                               Vocabulary#5

mass: the amount of matter in an object.

 Volume: the amount of space an objects takes up.

Weight: (on Earth)a measure of the force of gravity between Earth and an object.

density: a measure of how tightly packed matter is ; the amount of mass contained in a given volume.

buoyancy: the upward push on an object by the liquid (or gas)the object is placed in.

conduct: allow heat or electricity to flow throw through readily

insulate: not allow heat or electricity to flow through readily.

martes, 28 de septiembre de 2010

Colors of Light

                                                                               vocabulary #3
prism: a cut piece of clear glass(or plastic)with two opposite sides in the shape of a triangle or other geometric shape.

spectrum: a band of colors produced when light goes through a prism.

primary color: red,green,or blue;mixing these colors can produced all the colors of the spectrum.

primary pgment: magenta,cyan,yellow;material with anyof these colors absoves one primary color of light and reflects the other two.

Light and lenses

                                                                               Vocabulary#2
opaque: completely blocking light from passing through.

transparent: letting all light through,so that objects on the other side can be seen clearly.

translucent: letting only some light through,so that objects on the other side appear blurrry.

polarization: allowing light vibrations to pass through in only one direction.

refraction: the bending of light rays as they pass from one substance into another.

convex lens: a lens that curves outward(is thicker at the middle than at the edges)and brings light rays together.

concave lens :a lens that curves inward(is thicker at the edges than at the middle)and spreads light rays apart.

Light and mirrors

                                                        vocabulary #1

bioluminescence:light produced by living organisms.

light ray: a straight-line beam of light as it travels outward from its source.

Law of reflection: the angle of an incoming light ray equals the angle of the reflected ray.

concave mirror : a mirror thatcurves in on the shiny side.

convex mirror : a mirror that curves out on the shiny side.

martes, 7 de septiembre de 2010

The Solar System

The Solar System


Introduction

The Solar System consists of the Sun and those celestial objects bound to it by gravity, all of which were formed from the collapse of a giant molercular cloud approximately 4.6 billion years ago. The four smaller inner planets, Mercury, Venus, Earth and Mars, also called the terrestrial planets, are primarily composed of rock and metal.
The four outer planets, the gas giants, are substantially more massive than the terrestrials. The two largest, Jupite and Saturn, are composed mainly of hydrogen and helium; the two outermost planets, Uranus and Neptune, are composed largely of ices, such as water, ammonia and methane, and are often referred to separately as "ice giants".

The principal component of the Solar System is the Sun, that is a star similar to other stars in the night sky. It appears so large and bright to us because it is much closer to Earth. The Sun is composing mostly of hydrogen and helium.

Contents

The objects around the Sun include eight planets:
1. Mercury: is the closest planet to the Sun and the smallest planet in the Solar System. It has no natural satellites, and its only known geological features besides impact craters are lobed ridges or rupes.
2. Venus is close in size to Earth, and like Earth, has a thick silicate mantle around an iron core, a substantial atmosphere and evidence of internal geological activity. It has no natural satellites.
3. Earth: is the largest and densest of the inner planets, the only one known to have current geological activity, and is the only place in the universe where lige is known to exist.
4. Mars: is smaller than Earth and Venus. It possesses an atmosphere of mostly carbon dioxide with a surface pressure of 6.1 millibars. Its surface, peppered with vast volcanoes and rift valleys. Its red colour comes from iron oxide (rust) in its soil. Mars has two tiny natural satellites (Deimos and Phobos).
5. Jupiter, at 318 Earth masses, is 2.5 times the mass of all the other planets put together. It is composed largely of hydrogen and hellium It has 63 Known satellites. The four largest, Ganymede, Callisto, Io and Europa.
6. Saturn, distinguished by its extensive ring system, has several similarities to Jupiter, such as its atmospheric composition and magnetosphere.The rings of Saturn are made up of small ice and rock particles. It has 62 confirmed satellites; two of which, Titan and Enceladus, show signs of geological activity.
7. Uranus, is the lightest of the outer planets. Uniquely among the planets, it orbits the Sun on its side; its axial tiltt is over ninety degrees to the ecliptic. It has a much colder core than the other gas giants, and radiates very little heat into space. It has 27 known satellites, the largest ones being Titania, Oberon, Umbriel, Ariel and Miranda.
8. Neptune: though slightly smaller than Uranus, is more massive (equivalent to 17 Earths). It radiates more internal heat, but not as much as Jupiter or Saturn. It has 13 known satellites.

Conclusion:
Our solar neighborhood is an exciting place. The Solar System is full of planets, moons, asteroids, comets, minor planets, and many other exciting objects.

Our planets Earth is part of the Solar System, and It is unique that have live. Other planets has gas and all is rocks, where the lives is not good.

All eight planets can be seen with a small telescope; or binoculars. And large observatories continue to provide much useful information. But the possibility of getting up close with interplanetary spacecraft has revolutionized planetary science. Very little of this site would have been possible without the space program.