Download Glossary

Glossary
Adaptation - a change in structure, function, or form that improves the chance of survival for an organism
within a given environment.
Asteroid – a meteoroid found in the asteroid belt – tends to be large.
Asteroid Belt – a large belt of meteoroids found between Mars and Jupiter.
Biology – The study of living organisms.
Comet – a celestial body made up of ice and silicates that is only visible from Earth when it is near the sun,
sublimates, and forms a tail.
Crater – a large pit or hole created when a meteor hits the surface of a planet or moon.
Crater Floor – the bottom of the crater which is either flat or curved.
Crater Rim – the highest point of the crater, along the edge of the bowl.
Crater Wall – the sides of the crater bowl.
Crystal – a mineral that has formed a specific pattern of straight edges and perfect angles.
Diameter – the length of a straight line passing through the center of a circle or sphere, edge to edge.
Dichotomy – a choice between two options that contradict one another. In a dichotomous key, two questions
are asked about an item in order to help classify it.
Ejecta – crushed or melted rock that is ejected from the meteor impact site.
Element – any substance that cannot be broken down into a simpler one by a chemical reaction. There are
110 known elements – all matter is made from combinations of these.
Evaporate – the process in which a liquid turns into a gas.
Extremophile – an organism that lives in extreme environmental conditions (examples include living in
extreme hot, cold, dry, high pressure or radioactive environments).
Friction – the process of producing heat by rubbing two objects against one another.
Geology – the study of rocks and minerals and the naturally occurring surface formations of planets and
moons.
Geothermal – heat produced by a planet’s interior core.
Gravity – forces of attraction between two bodies.
Igneous Rock – a rock that has formed from melted rock that has cooled inside or outside the Earth.
Lander – a probe that lands on a planet but does not move from its landing site.
Martian – anything native to the planet Mars i.e. a rock from Mars is a Martian rock.
Metamorphic Rock – a rock that has changed from one type to another because of intense heat and pressure.
Meteor – the trail of light seen as a meteoroid burns from the friction of entering a planet’s atmosphere.
(often referred to as a “shooting star”)
Meteorite – any piece of a meteoroid that survives after the meteoroid has crashed on the surface of a planet
or moon.
Meteoroid – stone or metal debris fragments formed when a comet or asteroid disintegrates.
Microorganism – a very small animal or plant seen with the aid of a microscope.
Mineral – a pure solid formed naturally on Earth
Model – an object that represents another object or idea.
Nutrient – nourishment necessary for life and growth.
Orbit – the path taken when one body in space circles around a larger body in space.
Organism – any living thing i.e. an animal, plant, bacteria, fungus or protozoa.
Probe – a non-manned spacecraft that travels into space to explore planets, moons, asteroids, comets, stars
and other galaxies.
Rays – the streaks that begin at the rim of a crater and extend outward from the impact site like rays of the
sun.
Rover – a vehicle operated by remote control used to explore remote places that humans cannot safely travel
to, like the surface of Venus or Mars.
Satellite – any object that revolves around a larger object i.e. the moon revolves around the Earth and Hubble
Space Telescope revolves around the Earth.
Sedimentary Rock – a rock formed by rock particles (small bits and pieces of rocs) that have been deposited
by ice, water, or wind and then consolidated by pressure.
Solar System – the Sun and the planets, moons, asteroids, meteoroids and comets that revolve around the
Sun.
Universe – all matter and energy that exists in the vastness of space. Galaxies, stars, solar systems and the
space between them make up the universe.