Unit 9 Vocabulary – Define the words and draw the pictures.
1. rotational axis – the line on which an object rotates
2. autumnal equinox – around March 21st when the plane of
Earth's equator passes through the center of the Sun, making night
and day of approximately equal length all over the planet.
3. vernal equinox - around September 23rd when the plane of
Earth's equator passes through the center of the Sun, making night
and day of approximately equal length all over the planet.
4. rotate –
5. revolve -
a spinning motion
move in a circle on a central axis
6. solstice – when the Earth’s rotation axis is tilted directly toward or
away from the sun
7. summer solstice - June 21 is the summer solstice in the
Northern Hemisphere and marks the beginning of summer for the
earth north of the equator.
8. winter solstice - December 21 is the beginning of winter in the
Northern Hemisphere and summer in the Southern Hemisphere. It is
the shortest day of the year and the longest night.
9. new moon -
Occurs two weeks after the full moon. The
Moon is positioned between the Sun and Earth. The side of the Moon
visible from Earth is not illuminated.
10. waxing crescent -
Occurs after the new moon. Only the
right sliver of the Moon is illuminated.
11. first quarter moon -
Occurs after the waxing crescent.
Only the right quarter of the Moon is illuminated. From Earth, it appears to
be exactly the right half.
12. waxing gibbous -
Occurs after the first quarter. The
amount of the Moon illuminated is increasing.
13. full moon -
The Earth is positioned between the Sun and
Moon; this occurs two weeks after the new moon. The side of the Moon
visible from Earth is illuminated.
14. waning gibbous -
Occurs after the full moon. The
amount of the Moon illuminated is decreasing.
15. third quarter moon -
Occurs after the waning
gibbous. Only the left quarter of the Moon is illuminated. From Earth, it
appears to be exactly the left half.
16. waning crescent -
Occurs after the third quarter. Only
the left sliver of the Moon is illuminated.
17. eclipse – the covering of one celestial body by another
18. solar eclipse -
The Moon moves directly
between the Sun and Earth. The Moon casts a shadow on the Earth; this
only occurs with a new moon.
19. lunar eclipse -
The Earth, Sun, and
Moon are directly lined up in the center. The Earth casts a shadow on the
Moon; this only occurs with a full moon.
What causes tides? The moon's gravitational pull on the Earth causes
water levels in the oceans to rise and fall in a consistent, predictable
fashion.
20. high tide - the point at which the water level in a specific
location reaches its highest point
21. low tide - the lowest water level in a specific location
22. neap tide - a tide just after the first or third quarters of the moon
when there is the least difference between high and low water
23. spring tide –
tides that occur when the sun and
moon are directly in line with the earth and their gravitational pulls
reinforce each other. Produces the highest high tides and the lowest
low tides