Earth Science Flashcards Preview

It is the scientific study of the Earth, its history, composition, and structure done mainly through the study of rocks.

The topmost and thinnest layer of the Earth. It varies in thickness, from 10km underneath oceans to 80 km underneath mountains and mountain ranges. It is roughly 1% of the Earth’s volume.

It is 3,500km thick and is composed mostly of iron, calcium, and magnesium. It comprises approximately 80% of the Earth’s volume.

It is about 2,300km thick, is made up of a liquid nickel-iron alloy that surrounds a solid inner core with a radius of about 1,200km. It is found at the center of the Earth.

This is located between the upper mantle and the lower part of the crust, which carriers 30 plates that hold the major continents of the Earth.

These rocks are formed by the hardening of molten material. Much of this molten material is magma, or melted rocks underneath the surface of the earth. When magma is released through a volcanic reaction, it becomes lava that hardens into _______. Pumice and granite are common examples.

These are formed by the joining of separate particles, which may range from mud, sand, to gravel, that are compressed together over time. Shale, limestone, and soft coal are common examples.

These are formed over long periods of time because of changes in pressure or temperature. Both igneous and sedimentary rocks can become ________ over time. Marble, slate, and hard coal are examples.

This is the study of the atmosphere and all atmospheric phenomena, including weather. The Earth’s atmosphere, which is the mixture of gases surrounding it, is composed of five layers.

Here is where all weather occurrences take place. It can range from 6 to 17 kilometers thick and contains much of the air surrounding the Earth.

It is found above the troposphere, where the temperature can drop down to as low as -60° Celsius. It’s upper parts of the contains the ozone layer.

It s thin layer of a reactive form of oxygen which helps protect the Earth from the ultraviolet rays of the sun.

It is 90 kilometers above the solid surface of the Earth, where the temperature is -90° Celsius. When meteorites fall into the Earth, it is where they begin to burn up and produce a tail, thus they become the ‘shooting stars’ we see at night.

This is a thin layer which reflects radio waves used for satellites and other types of communication. It rises up to 350 miles above the surface of the Earth. Experts still have not reached consensus whether it is a distinct layer of atmosphere or not.

This phenomena that take place on Earth are affected by 5 major factors: temperature, air pressure, humidity, clouds, and air masses.

The Earth, particularly the masses of land and the oceans, absorb almost half of the radiation that comes from the sun. Radiation causes heat that warms up the air above the land and water. Land absorbs heat more quickly than water, and it releases heat more quickly too. During the day, the land is warmer, but it is also cooler during the night. Areas near the equator also receive more sunlight, as the sun’s rays strike directly towards the center of the Earth, whereas regions in the North and South receive slanted rays, allowing colder temperatures.

It refers to the push of the air against the surface of the Earth. Cold air has greater pressure (high pressure) than warm air (low pressure). Air typically flows from high pressure areas to low pressure ones.

The movement of air is commonly known as ______.

Air pressure is measured by a device known as a ______

When water evaporates into the atmosphere, it becomes water vapor. The amount of water vapor in the air is known as _______.

It is the amount of vapor in the air as compared to the maximum amount it can contain at a certain temperature. 50 to 60% is still comfortable for many people.

_____, or the change from water vapor to liquid, takes place at the dew point, when relative humidity reaches 100%.

They are huge, white clouds that resemble popcorn. They indicate fair weather, but when they darken and increase in size, heavy rains are expected.

They are low and flat clouds that bring rain, sleet, snow, frozen rain, or all of them at once.

This stratus clouds that occur on the ground are called _____.

They are high, wispy clouds that indicate rain and snow.

An _____ exhibits the characteristics of the region over which it was formed. ______ formed over water are humid; those formed over land are dry. ______ in the northern region are cold; those over tropics are warm. When different _____ meet, fronts are formed.

This is created when a cold air mass meets a warm air mass. Cumulus clouds are formed and rains are expected to fall soon.

This is formed when a warm air mass meets a cold air mass, and cirrus clouds are formed.

This is formed between two similar air masses that push against each other, causing cloudy and sometimes wet weather that last for a week.

This is composed of the sun and smaller celestial bodies such as the planets, moons, asteroids, comets, and meteors. Most of its mass 99.8%, comprises the sun, which creates gravity that holds the smaller celestial bodies in place in their orbits.

It is the center of the solar system. It is a giant ball of super-heated gases produced by atomic reactions at its surface and core. Scientists believe that its core is 15 million degrees Celsius, and 4,000 to 15,000° Celsius at the surface. It is 109 times larger than Earth, with 1.4 million kilometers of diameter and a surface area 12,000 times greater than this planet’s. It is the most important part of the solar system, as long as life on Earth is concerned. It provides most of the heat and light energy that are needed to produce food, one of life’s most basic needs.

Although the sun appears massive relative to the other objects in the solar system, it is classified as a ________, a yellow dwarf star compared to other stars in the galaxy. A ________ is yellow and contains neutrally charged particles such as iron, calcium, and magnesium.

It is a non-luminous body not smaller than a comet or asteroid and is illuminated by nearby stars. There are 8 _____ in our solar system.

It is the only planet in this solar system where life is known to be possible. It rotates at an axis where it is tilted at an angle of 23 1/2 °. This explains why the hours of night and day are never equal, except on the first day of spring (vernal equinox) and the first day of autumn (autumnal equinox). The earth spins a complete rotation in 24 hours and travels one full revolution around the sun in 365 1⁄4 days.

The four inner planets are those nearest to the sun. They are called _________ because they have a size and composition similar to Earth, mostly solid rock and iron.

The four outer planets have compositions much like the sun’s, with mostly hydrogen, helium, and other gases making them up. The outer planets have liquid surfaces as a result of their very thick atmospheres, but they are believed to have solid cores. They are also surrounded by rings of ice crystals, dust, and rock fragments. The most remarkable of these rings are those of Saturn.

This are natural satellites that revolve around a planet. All planets except Mercury and Venus have their own moons. Earth has one, which is considered a primary factor for the occurrence of life.

This occurs when Earth comes between the sun and moon.

It occurs when Earth moves into the moon’s shadow, this the moon is between Earth and the sun. All light from the sun is blocked out for a short period of time.

These are minor planets that have orbits that sometimes cross Earth’s. Its majority in the solar system are found in the asteroid belt found between Mars and Jupiter. There are about 200 ______ within this area and their diameters range from as big as 60 miles to as small as 2/3 of a mile.

It is a body of ice and rock that travels in an orbit around the sun. When they approach the surface of the sun, the sun’s energy pushes its ice nucleus outward, thus forming a long, bright tail of gases that can sometimes be seen from Earth.

These are comets that takes more than 200 years to complete their orbits.

These are comets that take less than 200 years to complete their orbits.

The most famous of all comets named after Sir Edmund Halley. It is a short-period comet last seen in 1986 and is expected to be back in the middle of 2061.

It is a rock that enters Earth’s atmosphere. As it does, it burns up and produces a tail of fire, making it look like a ‘shooting star’.

Meteors that burn and fall to the ground are called _______.

This layer can extend up to several thousands of kilometers where temperatures can reach up to 2,000° Celsius.