PTE

the movement of a mass of rock, soil, or debris down a slope under gravity

molten rock that has reached Earth's surface through volcanic activity

a naturally occurring inorganic solid with an ordered internal structure and a characteristic chemical composition

a continuing movement of seawater in a particular direction within the ocean

an area of land almost surrounded by water but connected to a larger land area

a broad area of land that is mostly flat or gently rolling

the way people are spread among different locations within an area

water from rain, melting snow, or other sources that flows over land rather than soaking into the ground

connected with the countryside rather than towns or cities

the height of the sea's surface, often averaged over time and used as a reference for elevation

loose particles of rock, minerals, or organic material that are transported or deposited by water, wind, or ice

land considered in terms of its physical features, especially the shape and condition of its surface

the regular rise and fall of sea level caused mainly by the gravitational influence of the Moon and Sun

crossing the Atlantic Ocean or involving places on its opposite sides

a series of waves caused by a sudden displacement of a large body of water, often following an undersea earthquake

connected with towns and cities or the people and activities found in them

relating to volcanoes or produced by their activity

the continuous movement of water among the atmosphere, land, oceans, and living things through processes such as evaporation and precipitation

how bright a celestial object appears to an observer at a particular location

a region of space with a boundary called an event horizon, from inside which light cannot escape

a small icy body orbiting the Sun that can release gas and dust when warmed

a recognized pattern of stars in the sky, or the formally named sky region associated with it

a roughly circular depression in a surface formed by an impact

to join a spacecraft to another spacecraft or space station

to hide all or part of a celestial body by blocking light from it

a spacecraft's passage near a celestial body without landing on it or entering orbit around it

a large system of stars, gas, dust, and other matter held together by gravity

a spacecraft designed to descend to and operate on the surface of a planet or moon

to leave the ground at the start of a rocket's flight