Satellite		in the orbit of a satellite, the point at which it is farthest from the Earth
Moon		a star that has collapsed under gravity to the point that the electrons and protons have smashed together to form neutrons.
Meteoroid		a group of stars organized in a recognizable pattern.
Convective Zone		a small body from which a planet originated in the early stages of development of the solar system
Corona		a large celestial body that is composed of gas and emits light.
Galaxy		a large cloud of dust and gas in interstellar space; star is born there.
Kuiper Belt		any one of the 4largest satellites of Jupiter-Io, Europa, Ganymede, Callisto- discovered by Galileo in 1610
Mare		the innermost layer of the Sun’s atmosphere, visible surface of the Sun.
lunar eclipse		the zone of the sun’s interior that is between the core and the convective zone and in which energy moves by radiation.
Terrestrial Planet		the passing of the Moon through Earth’s shadow at full moon
Phase		a very large and bright star whose hot core has used most of its hydrogen.
Giant		an apparent shift in the position of an object when viewed from different locations.
Radiative Zone		the outermost layer of the Sun’s atmosphere.
Eccentricity		an object so massive and dense that even light cannot escape its gravity.
Nova		a dark area of the photosphere of the Sun that is cooler than the surrounding areas and that has a strong magnetic field.
Apogee		A luminous atmospheric phenomenon appearing as streamers or bands of light visible in the night sky in northern or southern hemispheres caused by charged particles from the sun entering the earth's magnetic field and stimulating molecules in the atmosphere.
Star		a collection of stars, dust, and gas bound together by gravity.
Nebula		the change in the illuminated area of the Moon as seen from Earth
Crater		a narrow band in the Hertzsprung-Russell diagram in which 90 percent of all observed stars are plotted.
Perigee		the theory that all matter and energy in the universe all came from one singularity that exploded and continues to expand.
Photosphere		one of the highly dense planets nearest to the Sun
Planetesimal		a celestial body that revolves around a body that is larger in mass; a natural satellite
Asteroid		an observed change in the frequency of a wave when the source or observer is moving.
Constellation		a planet that has a deep massive atmosphere (Jupiter, Saturn, etc.)
Galiean Moon		a small rocky object that orbits the Sun
Black Whole		a bowl shaped depression that forms on the surface of an object when a falling body strikes the object’s surface or an explosion occurs
Coronal Mass Ejection		an explosive release of energy that comes from the Sun and that is associated with magnetic disturbances on the Sun’s surface.
Meteor		a natural or artificial body that revolves around a larger celestial body
Big Bang		a bright streak of light that results when a meteoroid burns up in Earth’s atmosphere.
Oort Cloud		a star that suddenly becomes brighter.
Aurora		a small body of rock, ice and cosmic dust that follows an elliptical orbit around the Sun and that gives off gas and dust in the form of a tail as it passes close to the Sun
Prominence		the passing of the Moon between the Earth and the Sun; Moon’s shadow falls on Earth
Main Sequence		the time required for a body to complete a single orbit
Solar eclipse		in the orbit of a satellite, the point at which it is closest to the Earth
Sunspot		the degree of elongation of an elliptical orbit
Doppler Effect		the thin layer of the Sun that is just above the photosphere and glows a reddish color during eclipses.
Orbital period		the region of the Sun’s interior that is between the radiative zone and the photosphere and in which energy is carried upward by convection.
Chromosphere		the brightness of a star as seen from Earth.
Light-year		a rotating cloud of gas and dust from which the sun and planets formed
Apparent Magnitude		a spherical region that surrounds the solar system that extends from the Kuiper Belt to almost halfway to the nearest star, contains billions of comets.
Solar Flare		a large dark area of basalt on the Moon
Solar nebula		a relatively small, rocky body that travels through space.
Nuclear Fusion		the brightness a star would have at a distance of 32.6 light-years from Earth.
Cosmic Background Radiation		process by which nuclei of small atoms combine to form a new, more massive nucleus; process releases energy.
Cosmology		a part of coronal gas that is thrown into space from the Sun.
White Dwarf		a region of the solar system that starts just beyond the orbit of Neptune and contains dwarf planets and other small bodies made mostly of ice.
Gas Giant		radiation uniformly detected from every direction in space.
Absolute Magnitude		the study of the origin, properties, processes, and evolution of the universe.
Parallax		a loop of relatively cool, incandescent gas that extends above the photosphere.
Neutron Star		a small, dim, hot star that is the leftover center of an old star.
Comet		the distance that light travels in 1 year.