Download Glossary May 2011 Pg 1

GLOSSARY
Adaptation - A change in structure, function, or form that improves the chance of survival
for an organism within a given environment.
Asteroid - A large chunk of rock, metal or a mixture of both found in the asteroid belt.
Asteroid Belt - A large belt consisting of chunks of rock and metal found between Mars
and Jupiter.
Biology - The study of living organisms.
Comet - A celestial body made up of ice, gas 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 meteorite 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.
Dwarf Planet - A celestial body that is round, revolves around the Sun and does not clear
its orbit - Pluto is the most famous dwarf planet.
Ejecta - Crushed or melted rock that is ejected from the meteorite 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 which are
detrimental to most other organisms.
Friction - The process of producing heat by rubbing two objects together.
Galaxy - A large area of the universe that contains a large group of stars spinning around a
common center.
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.
Kuiper Belt - The area beyond Neptune that contains three dwarf planets (Pluto, Haumea
and Makemake) and thousands of comets.
GLOSSARY
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 as it enters 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 ot moon.
Meteoroid - Stone or metal debris fragments formed when a comet or asteroid
fragments.
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.
Oort Cloud - the theoretical area of the Solar System farthest from the Sun containing
millions of comets. Eris, the furthest dwarf planet, lies between the Kuiper Belt and the
Oort Cloud.
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.
Satellite - Any object that revolves around a larger object other than the sun - i.e. both
the moon and the Hubble Space Telescope revolve around the Earth.
Sedimentary Rock - A rock formed by rock particles (small bits and pieces of rocks) that
have been deposited by ice, water or wind and then consolidated by pressure.
Solar System - The Sun and all the planets, moons, asteroids, comets and debris that
revolves around the Sun.
Universe - All matter and energy that exists in the vastness of space. Galaxies, stars,
solar systems, rogue planets and the space between them make up the universe.