Earth and Space Science

Flashcards about Earth and Space Science

What are the three major types of evidence used by scientists to determine the age of Earth and objects on it?

Landforms, fossils, and radiometric dating.

How do the layers of sedimentary rock indicate relative age?

The youngest layers are at the top and the oldest layers are at the bottom.

How can the age of a fossil be determined in sedimentary rock?

By looking at the layer it is found in.

Name two radioactive isotopes used by scientists in radiometric dating.

Carbon-14 and uranium-235.

What is a half-life?

The amount of time it takes half of an isotope's atoms to change into another element.

What separates the gas giants from the terrestrial planets?

The asteroid belt separates the gas giants from the terrestrial planets

How long does it take Earth to complete one revolution and one rotation?

Earth completes one revolution around the sun every 365 days and one rotation every 24 hours

What is the difference between a solar eclipse and a lunar eclipse?

Solar eclipse: the moon blocks sunlight from reaching Earth. Lunar eclipse: Earth blocks sunlight from reaching the moon.

What causes tides?

The pull of the moon's gravity as Earth rotates on its axis.

What are spring tides?

Extra high and extra low tides caused when the sun is in line with the moon.

What are neap tides?

Minor differences in high and low tides caused when the sun and moon are perpendicular to each other.

What is a star?

A ball of gas that produces its own light and heat.

What is a constellation?

A recognized pattern of stars in the night sky.

What galaxy is our solar system a part of?

The Milky Way Galaxy.

Briefly explain the Big Bang theory.

All of the matter and energy in the universe was once contained in an area the size of an atom, and an enormous explosion (Big Bang) caused the matter and energy to rapidly expand outward.

What is a nebula?

A cloud of gas and dust where a star forms.

What causes main sequence stars to release heat and light?

The fusion of hydrogen (H) atoms into helium (He) atoms.

What is a supernova?

A sudden explosion in which supergiant stars die

What are the three main layers of Earth's interior?

Crust, mantle, and core.

What are the two types of crust?

Oceanic crust: dense, dark, finely textured rock called basalt. Continental crust: mainly granite, a lighter, less dense rock with larger crystals than those found in basalt.

What is the asthenosphere?

A soft layer of the mantle where material can flow freely.

What are convection currents?

Hot currents of molten rock that cause the plates above them to move.

What are the three types of plate boundaries?

Transform, divergent, and convergent.

What are fold mountains?

Mountains made when one plate slides on top of another plate.

What is lava?

Magma that reaches Earth's surface.

What is a fault?

The break in the crust where earthquakes can occur.

What are the layers of Earth's atmosphere?

Troposphere, stratosphere, mesosphere, thermosphere, ionosphere, and exosphere.

What are the gases in Earth's atmosphere?

78% nitrogen, 20% oxygen, and trace amounts of several other gases, including hydrogen and carbon dioxide.

What are the greenhouse gases?

Water vapor, carbon dioxide, and methane.

What is global warming?

A gradual increase in the temperature of Earth's atmosphere that can lead to climate change.

What chemicals cause the depletion of ozone?

Chlorofluorocarbons (CFCs).

What is weathering?

Breaking down or dissolving minerals and rocks on Earth's surface.

What is erosion?

Wind, water, and gravity transporting bits of rocks and minerals away.

What is wind and what causes it?

The movement and flow of gases on Earth's surface. It is caused by the uneven heating of the surface by the sun.

What are prevailing winds?

Winds that regularly blow from a single direction over a specific area of Earth.

What is the Coriolis effect?

Earth's rotation generating a circulation pattern that makes wind systems twist counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere.

What is the average salinity of ocean water?

3. 5%.

How do currents affect ocean temperature ?

Currents flowing near the surface of the oceans transport warm water from the equator to the poles and cool water back toward the equator.

What is upwelling?

When winds push surface water away from the shore, deep currents of cold water rise to take its place.

What are zooxanthellae?

Microscopic, symbiotic algae that live in the bodies of coral.

Briefly explain the nitrogen cycle.

Nitrogen moves from the air to the soil, into living things, and back into the air.

Briefly explain the carbon cycle.

A system involving living things and the nonliving matter in Earth's crust, oceans, and atmosphere, in which carbon is transferred from one part of the environment to another.

Briefly explain the oxygen cycle.

The movement of oxygen within the atmosphere, organisms, and nonliving matter on Earth's crust.

Briefly explain the water cycle.

The continuous process of transporting water from the oceans to the atmosphere, then to the land, and then returning it to the oceans.

What is a natural hazard?

The threat of a natural event that can have a negative effect on organisms and the environment.

Name some structural mitigation techniques for natural hazards

Building dams, dikes, levees, and containment ponds to hold water or slow its flow, and structures like storm shelters

Name some nonstructural mitigation techniques for natural hazards.

Land use regulations, building codes, and zoning ordinances.

What are renewable resources?

Those that will never run out, either naturally or through proper management.

What are nonrenewable resources?

Those that will eventually run out; they have a finite supply.