Planet-  An object that orbits the sun and is large enough to have become rounded by its own gravity, and has cleared the area of its orbit

Satellite-  A body that orbits a planet. 

Meteor- A streak of light produced when a small object burns up entering Earths atmosphere. Can see almost every night 

Comet- Cold mixture of dust and ice that gives off a long trail of light as it approached the sun. Rarer than meteors 

Star- : Giant ball of hot gas, mainly composed of hydrogen and helium. Position of stars relative to each other do not seem to change

Constellation- A pattern or group of stars that people imagined to represent a figure, animal or object.

Polaris-  North star. Is fixed in the night sky

Zodiac-Move through a narrow band in the sky called

Rotation- The earth spinning on its axis one time - 1, 24 hour day and night cycle

Revolution- the movement of one object around another object in space

Orbit-- path in which a revolution occurs

Ellipse-Earth’s orbit is an elongated circle- 

Kepler’s law- When the planet is closer to the sun it moves faster around its orbit, and when it is further away ti moves slower.

Apogee-(Aphelion) that point in the earth elliptical orbit where the Earth and Sun are farthest apart

Perigee- (Perihelion) that point in the Earth elliptical orbit where the Earth and Sun are closest together

Equinox- A day when Earth's rotation axis is leaning along Earth's orbit, neither toward or away from the sun.

Solstice-The day when Earth's rotation axis either toward or away from the sun.

Gravity- decreases rapidly as the distance between the 2 objects increases

Law of universal gravitation-  Every object in the universe attracts every other object. The strength of the force of gravity between 2 objects depends on two factors. Mass and distance between them.

Mass- amounts of matter in an object

Weight- Measure of the force of gravity on an object 

Inertia- Tendency of an object to resist change in motion

Newton’s first law of motion- An object at rest will remain at rest, and an object in motion, will remain in motion at a constant speed and direction, unless acted upon by a force.

Eclipse- When an object in space comes between the sun and a third object it casts a shadow on that object

Solar eclipse- When the moons shadow hits the earth

Lunar eclipse- Occurs at a full moon when Earth is directly between the moon and the sun, When the umbra of earths shadow hits the moon

Umbra- Very darkest part of the moons shadow. 

Penumbra- : Less dark shadow than Umbra, larger. Part of the sun is visible from Earth. People in this ara would see a partial eclipse

Total eclipse- When the entire sun is hidden by the moon a total eclipse occurs.

Partial eclipse- When only part of the sun is hidden by the moon. 

Annular eclipse- When moon is too far away for it to completely block out the sun but allows the sun to remain visible around the edges of the moon.

Tide-  The rise and fall of the ocean water that occurs every 12.5 hours.

High tide- Moon’s gravity pulls the water on the Earth nearest to the moon towards it. 

Low tide- Water on  the sides of the earth perpendicular to those two areas closest to and farthest from the earth are low tide areas of the earth

Spring tide-A tide that happens during a new or full moon, and has the strongest tides.

Neap tide- the lowest tide

Maria-  Dark, flat areas which are hardened rock formed from huge lava flows that occurred 3-4 billion years ago. ‘Lunar Seas’’

Crater- Large round pits caused by the impact of meteoroids or chunks of rock or dust from space,

Highland- Mountains on the moon

Rilles-Valleys on the moon

Collision theory- This is the theory that best fits the evidence when the earth was veery young and consisted of molten rock, a collision with an object about the size of Mars occurred and flung material into orbit.

Full moon

New moon

Waning Gibbous

Waxing Gibbous

Third quarter

First quarter

Waning crescent

Waxing crescent