EMS System- Astronomy

the path of an object as it revolves around another object in space

the time required for a body to complete a single orbit

nearly circular; range of distance from the sun: 147-152 million km; Earth is closest to the sun in January

the movement of an object around another object

the spinning of an object on its axis in space

24 hours

caused by the tilt (23.5 degrees) of Earth on its axis as it revolves around the Sun

the day when Earth's rotational axis is the most toward or away from the Sun; June 20 or 21 & December 21 or 22

the day when Earth's axis is not learning toward or away from the Sun; March 20 or 21 & September 22 or 23

seems to move across sky from east to west

27.3 Earth days on its axis = 1 lunar day.

time for moon to complete one full revolution around Earth; 27.3 Earth Days

time for moon to complete a phase cycle (new moon to new moon); also called a lunation; 29.5 Earth days

Moons Revoloution

the synchronization between orbital period and period of rotation of one body (such as the Moon) orbiting another body (such as the Earth)

mars sized planet hits Earth (Theia)

explains difference in appearance and crustal thickness of the near and far side of moon; soon after the Moon's formation

dark-colored, relatively flat regions of the Moon formed when ancient lava flowed up through the Moon's crust and solidified

lit part of the Moon or a planet that can be seen from Earth;

occurs when more of the Moon's near side is lit each night

occurs when less of the Moon's near side is lit each night

phase that occurs when the Moon is between Earth and the Sun

the phase where half of the Moon's near side is illuminated by the Sun

the phase where greater than half (but not a full moon) of the Moon's near side is illuminated by the Sun

seems to move across sky from east to west

5 degrees; this is why eclipses do not occur every month

counter-clockwise

occurs at a full moon when Earth is directly between the moon and the Sun

occurs when the Moon passes directly between the Sun and Earth and casts a shadow over part of Earth

the straight line configuration of 3 celestial bodies (as the sun and earth and moon) in a gravitational system

the darkest part of the moon's shadow

the lighter part of a shadow where light is partially blocked

the periodic rise and fall of the sea level under the gravitational pull of the moon

a tide just after a new or full moon

a tide just after the first or third quarters of the moon when there is the least difference between high and low water

we view the same side of the moon

Earth-Moon-Sun system

a mechanical model of the EMS or solar system used to represent relative positions and motions