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the study of all physical objects beyond Earth.


a system for organizing time. most calendars organize time within a single unit called a year.


is the time required for the Earth to revolute the sun once.


roughly the amount of time required for the Moon to orbit/revolute the Earth once.


the time required for the Earth to rotate once on its axis.

leap year

a year in which an extra day is added to the calendar


a section of the sky that contains a recognizable star pattern


in astronomy, the angle between an object in the sky and the horizon


an imaginary point in the sky direction above an observer on Earth


the line at which the sky and Earth appear to meet


a unit of length equal to the distance that light travels through space in 1 year.

Solar System

Is composed of the sun (a star) and the planets and other bodies that travel around thee sun.


dust and gas clumb together in huge intersellar clouds are so big that light takes many years to cross them.

Solar Nebula

the name of the nebula that formed into our solar system.


when bits of dust within the solar nebula stuck together when the collided, forming the tiny building blocks of the planets.


The spinning motion of a body on it's axis


The elliptical path a body takes as it travels around another body In space

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