Earth Sun Moon System

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Star Noun

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[star]

Back

Star

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A giant ball of superheated gas, or plasma, composed of hydrogen and helium that shines due to nuclear fusion.

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Example: Stars are giant balls of gas in the night sky, shining due to nuclear fusion.

Front

Planet Noun

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[plan-it]

Back

Planet

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A celestial body that orbits a star, is large enough to be rounded by its own gravity, and has cleared its orbital path.

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Example: The image shows Earth as a planet, highlighting its rotation with arrows, illustrating its orbit around the sun.

Front

Satellite Noun

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[sat-uh-lite]

Back

Satellite

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A celestial or artificial body that orbits a larger body in space, such as a planet or star.

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Example: The Moon orbits Earth, showing how a satellite moves due to gravity and velocity.

Front

Meteor Noun

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[mee-tee-or]

Back

Meteor

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A streak of light produced when a small piece of rock or ice burns up as it enters a planet's atmosphere.

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Example: A meteor streaks across the sky as it burns up entering Earth's atmosphere.

Front

Comet Noun

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[kom-it]

Back

Comet

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A celestial object made of ice and dust that develops a glowing tail as it approaches the sun.

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Example: A comet with a glowing tail approaching the sun, illustrating how it forms a tail as it nears the sun.

Front

Constellation Noun

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[kon-stuh-ley-shuhn]

Back

Constellation

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A group of stars forming a recognizable pattern that is traditionally named after a mythological figure, animal, or object.

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Example: The image shows the Orion constellation, illustrating how stars form a recognizable pattern named after a mythological figure.

Front

Geocentric Model Noun

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[jee-oh-sen-trik mod-l]

Back

Geocentric Model

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An early model of the solar system where Earth is at the center and all other celestial bodies orbit it.

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Example: The image shows Earth at the center with the Sun, Moon, and planets orbiting it, explaining the geocentric model.

Front

Heliocentric Model Noun

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[hee-lee-oh-sen-trik mod-l]

Back

Heliocentric Model

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A model of the solar system where the sun is at the center and Earth and other planets revolve around it.

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Example: The image shows the sun at the center with Earth orbiting around it, illustrating the heliocentric model.

Front

Astronomy Noun

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[uh-stron-uh-mee]

Back

Astronomy

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The scientific study of celestial objects, space, and the physical universe as a whole.

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Example: A telescope helps us observe celestial objects like planets and galaxies, key to studying astronomy.

Front

Ellipse Noun

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[ih-lips]

Back

Ellipse

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An oval shape that describes the path of a planet's orbit around the sun in the heliocentric model.

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Example: The image shows Earth's elliptical orbit around the sun, highlighting distances at aphelion and perihelion.