Question | Answer |
astronomy | the study of the moon, stars, and other objects in space |
axis | imaginary line that passes through Earth's center and the North and South poles |
rotation | the spinning of earth on its axis |
revolution | the movement of one object around another |
orbit | path earth follows as it revolves around the sun |
calendar | a system of organizing time that defines the beginning, length, and divisions of a year |
solstice | when the sun is farthest north or south of the equator |
equinox | means "equal night". when day and night are each about 12 hours long everywhere on earth |
force | a push or pull |
gravity | a force that attracts all objects toward each other |
law of universal gravitation | law that states that every object on the universe attracts every other object |
mass | the amount of matter in an object |
weight | the force of gravity on an object |
inertia | the tendency of an object to resist a change in motion |
Newton's first law of motion | says that an object in rest will stay at rest and an object in motion will stay in motion unless acted upon by an unbalanced force |
phases | the different shapes of the moon you see from earth |
eclipse | when an object in space comes between the sun and a third object, it casts a shadow on that object |
solar eclipse | occurs when a new moon blocks your view of the sun |
umbra | the very darkest part of the moons shadow |
penumbra | the larger less dark part of the shadow |
lunar eclipse | occurs at a full moon when earth is directly between the moon and the sun |
spring tide | tide with the greatest distance between consecutive low and high tides |
neap tide | tide with the least difference between consecutive low and high tides |
new moon | when the sunlit side faces away from earth |
waxing cresent | the portion of the moon you can see is wacing or growing, into a cresent shape. (right side) |
first quarter | you can see half of the sunlit side of the moon. (the right side) |
waxing gibbous | the moon continues to wax. the visible shape of the moon is called gibbous |
full moon | the entire sunlit side faces earth |
waning gibbous | the portion of the moon you can see wanes, or shrinks. |
third quarter | you can see half of the moons lighted side (the left side) |
waning cresent | you see a cresent once again. (left side) |
low tides | occur between the two higher tides. |
high tides | the moons gravity causes high tide on the sside closest to the moon |
29.5 days | about how long it takes a new moon to occur again after the last new moon |
27.3 days | about how long it takes the moon to revolve once around the earth |
telescope | a device built to observe distant objects by making them appear closer |
maria | dark flat areas on the moons surface |
craters | large round pits |
meteoroids | chunks of rock or dust from space |
rocket | a device that expels gas in one direction to move in the opposite direction |
thrust | the reaction force that propels a rocket forward |
velocity | the speed in a given direction |
orbital velocity | the velocity a rocket must achieve to establish an orbit around earth |
escape velocity | the velocity a rocket must reach to flu beyond a planets gravitational pull |
satellite | an object that revolves around another object in space |
sputnik I | launched by the soviets to begin the space race |
Laika | the first dog in space |