|
|
Space
Exploration:
Glossary
of Terms
absolute magnitude: The brightness of a
star if it were a standard distance from the Earth. apparent
magnitude: The brightness of a star as it actually appears to a person from the
surface of the Earth. asteroid:
a small rock-like object that travels through space. asteroid
belt: The concentration of asteroids found between the orbits of Mars and
Jupiter. astronomical
unit: a distance measured that is equal to the average distance between the
Earth's center and the Sun's center. It measures about 149 599 000 km in
distance. astronomy:
The scientific study of celestial bodies. atmosphere:
The gaseous envelope that surrounds a planet. atom:
The basic building block of matter made up of protons, electrons, and/or
neutrons. atomic
mass: The average mass of an atom of an element. aurora
borealis: The shifting patterns of coloured light that appear in the night sky in
the northern latitudes. This is a result of the collisions between charged
particles and molecules in the upper atmosphere. aurora australanis: Like the aurora borealis, but located in the southern latitudes. axis:
An imaginary line that goes through the center of the Earth through the poles. Big
Bang Theory: A scientific explanation regarding the beginning of the formation
of the universe. binary
stars: two stars that orbit around each other. biosphere:
The part of the Earth that supports life. black
dwarf: The final phase in the life of a star, usually after the white dwarf
stage. black
hole: an object believed to be so dense that it attracts all other celestial
objects, including light energy towards it. celestial
bodies: includes all stars, planets, asteroids, and natural satellites.
celestial
object: a naturally occurring object in space such as a star, planet, etc. celestial
sphere: an imaginary sphere believed to hold all components of the universe
together. Cepheid
variable: a star that pulses and changes its brightness in a regular cycle. comet:
a ball made of ice and dust particles that travels in an orbit around the Sun.
Once it reaches a distance closer tto the Sun, it glows and begins to melt,
forming a tail that points away from the Sun. constellation:
groups of stars that form patterns or shapes in space. corona:
an irregularly shaped halo that forms around the Sum. density:
the mass per unit volume of a substance. This can be measured in Kg/m. or g/cm Doppler
Effect: the apparent change in speed of sound, light and other energy waves as a
result relative motion between the observer and the wave source. element:
a pure substance that cannot be broken down into simpler substances. extra-solar
planet: a planet that orbits a star other than the Sun. extra-terrestrial life: life that is thought to exist outside of the Earth's biosphere. fact:
a verifiable statement or event that is known to have really occurred. fission
products: the atoms remaining after nuclear fission takes place. These atoms are
highly radioactive. galaxy:
The huge collection of gases, dust, as well as all celestial bodies that make up
a given area in the universe. gas
giant: A planet that has a huge atmosphere that is made up of mostly hydrogen
and helium gases. gamma
ray burst: a powerful pulse of gamma rays, normally from space. gamma
ray camera: a device used to detect gamma rays. gamma
rays: energy waves emitted from nuclear reactions. They have the shortest
frequency and highest energy of all waves in the electromagnetic spectrum. geocentric
model: refers to the model of the solar system in which the Earth is located in
the center. geomagnetic
storm: results when particles sent from the Sun from solar flares are drawn
towards the Earth by its magnetic field. geosynchronous
orbit: the orbit a satellite takes around the Earth. This orbit takes about 24
hours and is located the same distance from the surface of the Earth in
synchrony with the Earth's rotation. Global
Positioning System, GPS: a system that uses satellites for the purpose of search
and rescue missions as global
warming: resulting from the trapping of heat by the atmosphere created by the
accumulation of greenhouse gases. globular
cluster: a collection of stars (100 000-1 000 000) that form a spherical shape .
gravity:
a force that attract objects to each other. Usually, a larger object exerts a
gravitational force on a smaller object. Greenhouse
Effect: a natural process in which heat from the sun is trapped by the Earth's
atmosphere near the Earth's surface. Greenhouse
gases: a gas that traps heat in the atmosphere, for example, carbon dioxide. Hubble
constant: the ratio of the speed at which galaxies are receeding away to the
distance away of those galaxies. Hubble's
Law: states that galaxies are moving apart at rates that increase in direct
proportion to the distance between them hydrosphere:
that part of the Earth that is made up of water. Inner
Planets: The four planets that are closest to the Sun. They include Mercury,
Venus, Earth and Mars. International
Space Station, ISS: a space station that was created with the help of space
agencies from such countries as Brazil, Canada, Europe, Japan, Russia, and the
United States of America. inter-stellar
medium: the space between the stars and the material it contains. ion:
an atom that has become charged as a result of the gain or loss of electrons. light
year: the distance that light rays travel in one year. (9.46 X 10
km) low
Earth orbit: an orbit just above the Earth's atmosphere. luminosity:
the total amount of energy a star radiates per second. magnetosphere:
the space surrounding a celestial body such as the Earth that exerts a magnetic
field. main
sequence: a narrow band of stars in the Hertsprung-Russell diagram that
represents most stars in the universe. mass:
the amount of substance in an object. matter:
anything that has mass and takes up space. meteor:
a bright streak of light that is a result of a meteor travelling through the
Earth's atmosphere. The light is caused by the friction between the rock surface
and the molecules that make up the Earth's atmosphere. meteoroid:
a lump of rock or metal from space that gets trapped by the Earth's gravity and
is pulled downwards towards the Earth's surface. meteorite:
the part of the meteor that actually reaches the Earth's surface. meteorology:
the study of the Earth's atmosphere and weather conditions. microgravity:
the reduced effects of gravity on objects in space. Milky
Way: the galaxy that includes our solar system and appears as a cloudy white
haze in the night sky. mineral:
a naturally occurring compound or element found in the Earth's crust. model:
a presentation that is used to represent a thing or process observed. nebula:
A huge cloud of dust and gases found in space. It usually signifies the
beginning or ending of a star. neutron
star: an extremely dense star made up of neutrons. A stage of a huge star when
it dies. non-luminous:
not emanating its own light by rather reflecting light from other light sources.
nuclear
energy: the release of huge amounts of energy as a result of the splitting or
fusion of atomic nucleii. nuclear
fusion: a process in which substances fuse to from new substances and releasing
large amounts of heat and light energy. nuclear
fission: a process in which substances are split apart releasing huge amount of
heat and light energy. observatory:
a building containing an open dome that houses a telescope through which
observations can be made on celestial objects. orbit:
a circular or elliptical path that a smaller object takes around a larger one. orbital
period: The time taken by an object as it orbits around another object. outer
planets: The planets that are located outside the inner planets in the solar
system. They include Jupiter, Saturn, Uranus, Neptune, and Pluto. outer
space: everything that is typically located outside the Earth's atmosphere. ozone:
a layer of oxygen in the form of O3 in the Earth's atmosphere that absorbs most
of the Sun's ultra-violet light. parallax:
the apparent shift in position of a celestial object nearby compared to the
distant background when it is viewed from two different locations. payload:
includes a satellite, a piloted spacecraft, or cargo launched into space. photosphere:
the layer of the Sun from which most of the Sun's light is generated. planet:
a large rock or gas body that revolves around a star. planetary
nebula: a celestial object that resembles a planet surrounded by gases. planetary
system: group of planets that are in orbit around a star. pulsar:
a form of neutron star that emits pulses of very high energy radio waves. quasar:
a star like object that emits radio waves. radar:
a device that emits radio waves for the purpose of locating objects by bouncing
the radio waves off these objects. radio
telescope: a device that is used to detect radio waves from space. red
dwarf: a small cool star that does not generate much energy. red
giant: a star near the end of its life that has become red as a result of the
burning off the remaing hydrogen gas. red
shifted: a movement towards the red end of the light spectrum. reflecting
telescope: an optical device with a concave mirror, used to gather light and to
make objects that are far away appear larger. refracting
telescope: an optical device with lenses that focus light to make distant
objects appear larger. remote
sensing: the use of imaging devices to make observations from a distance, such
as from a satellite in low Earth orbit. retrograde
motion: the actual or apparent movement of a celestial object that is opposite
to that of the typical east-west direction. satellite:
an object that travels in an orbit around a larger object. This includes moons
as well as artificial satellites. SETI
(Search for Extra-terrestrial Intelligence): a term to represent agencies
dedicated to the search for radio signels from space indicating the existence of
life beyond that of Earth's. solar
flare: the high temperature eruption of gases emanating from near sun spots from
the sun's surface. They are known to cause disruptions to the Earth's magnetic
field as well as disturbances in radio signals. solar
mass: a unit for comparison for measuring the mass between stars. Our Sun has a
solar mass of one. solar
nebula theory: the belief that many of our astronomers hold for the creation of
our solar system. solar
plane: the imaginary plane from the equator of the sun in which our planets
orbit except Pluto. solar
prominence: the huge eruption of hot glowing gases from the Sun's surface. solar
system: includes all objects that orbit around the Sun including the nine known
planets, their moon, asteroids, etc. solar
wind: streams of electrically charged particles that travel from the sun into
space. It usually results from the activity associated with solar flares and sun
spots. space
probe: an un-piloted spacecraft that is used to make observations and send back
information to Earth regarding these observed objects. spacecraft:
a space vehicle that is designed to travel in the vacuum like vastness of space.
spectroscope:
a device used to split light energy into it component parts. spectrum:
a band of colour that results when light is refracted or split into it's
component parts. star:
a huge ball of mainly hydrogen and helium gases that emits large amounts of
light and heat. star
cluster: a group of strs that are found relatively close to each other and
travel together. Sun:
The star in which Earth and the other eight planets revolve around. sun
spot: a dark patch found on the Sun's photosphere. supernova: a huge explosion that results
when a massive star nears the end of its life. theory:
an explanation of an event that has been supported by consistent and repeated
experimental data and therfore has gained acceptance by the majority of
scientists. tidal
range: the difference in the water level between high tide and low tide. universe:
includes all matter and space that exists everywhere. visible
spectrum: a small part of the electromagnetic spectrum that can be viewed as a
band of colours. white
dwarf: a small star created from the remaining material from a red giant after it dies. x-ray:
a part of the electromagnetic spectrum that has very short wavelengths and has
the ability to penetrate substances such as skin and muscle. zodiac
constellation: a constellation that is named after an animal. From the Greek
word "zodion" meaning animal sign. |