Copyright Glencoe/cGraw-Hill, a division of the cgraw-hill Companies, nc. ame Date Class he un-arth-oon ystem 25 Directions: Circle the term in the puzzle that fits each clue. he terms read across or down. hen write the term on the line. 1. occurs when the un is directly over the equator 2. earth s spinning that causes night and day 3. solstice that occurs in December in the southern hemisphere 4. round, three-dimensional object whose surface at all points is the same distance from its center 5. a complete orbit made by arth around the un 6. imaginary line around which arth spins 7. property of arth that causes seasons 8. shape of arth s orbit 9. solstice that occurs in December in the northern hemisphere 10. time it takes arth to rotate on its axis 11. time it takes arth to revolve around the un 12. two times during the year, the un is directly over this imaginary line that circles arth halfway between the poles. 13. occurs when the un reaches its greatest distance north or south of the equator arth eeting ndividual eeds einforcement 1 V X Q X H Z W C W D Y Y
ame Date Class ection 1 ote-taking Worksheet arth he un-arth-oon ystem. roperties of arth people used to think that arth was flat and at the of the universe. 1. arth is now known to be a round, three-dimensional. a. imaginary vertical line around which arth spins b. the spinning of arth around its axis that causes day and night 2. arth has a field with north and south poles. 3. agnetic imaginary line joining arth s magnetic poles a. arth s magnetic axis does not with its rotational axis. b. he of magnetic poles slowly changes over time. B. Causes of seasons 1. arth s yearly orbit around the un a. arth s orbit is an, or elongated, closed curve. eeting ndividual eeds b. Because the un is not centered in the ellipse, the between arth and the un changes during the year. Copyright Glencoe/cGraw-Hill, a division of the cgraw-hill Companies, nc. 2. arth s causes seasons. a. he hemisphere tilted toward the un receives more hours than the hemisphere tilted away from the un. b. he period of sunlight is one reason summer is warmer than winter. 3. arth s tilt causes the un s radiation to strike the hemispheres at different. a. he hemisphere tilted toward the un receives more total than the hemisphere tilted away from the un. b. n the hemisphere tilted toward the un, the un appears in the sky and the radiation strikes arth more directly. C. the day when the un reaches its greatest distance north or south of the 1. solstice occurs June 21 or 22 in the northern hemisphere. 2. solstice occurs December 21 or 22 in the northern hemisphere. he un-arth-oon ystem 31
ame Date Class ote-taking Worksheet (continued) D. the day when the un is directly over arth s equator 1. Daylight and nighttime hours are all over the world. 2. equinox occurs on arch 20 or 21 in the northern hemisphere. 3. equinox occurs on eptember 22 or 23 in the northern hemisphere. eeting ndividual eeds ection 2. otions of the oon he oon arth s atellite 1. he oon on its axis. 2. he oon s rotation takes days with the same side always facing arth. 3. he oon seems to shine because it reflects. B. oon the different forms the oon takes in its appearance from arth 1. when the oon is between arth and the un and cannot be seen 2. phases more of the illuminated half of the oon that can be seen each night after the new moon a. First visible thin slice of the moon is a. b. phase half the lighted side of the oon is visible. c. more than one quarter is visible. d. ll of the oon s lighted side is visible during a. 3. phases less of the illuminated half of the oon is visible after the full moon. a. starts after a full moon when more than half of the lighted side is still visible b. nly half the oon s lighted side is visible during the phase. c. he last visible slice before a new moon is called the. 4. he oon completes its cycle of phases in about 29.5 days instead of 27.3 days because it is keeping up with arth s around the un. C. when arth or the oon casts a shadow on the other 1. the oon moves directly between arth and the un, shadowing part of arth. a. nder the, or darkest part of the shadow, a total solar eclipse occurs. b. partial solar eclipse happens in the lighter shadow on arth s surface called the. Copyright Glencoe/cGraw-Hill, a division of the cgraw-hill Companies, nc. 32 he un-arth-oon ystem
ame Date Class ote-taking Worksheet (continued) c. total solar eclipse is visible only on a small area of. 2. when arth s shadow falls on the oon a. f the oon is completely in arth s umbra, a lunar eclipse occurs. b. lunar eclipse when only part of the oon moves into arth s umbra, or the moon is totally in the penumbra c. total lunar eclipse is visible on the side of arth when the night is clear. D. he oon s surface has many depressions, or, formed from meteorites, asteroids, and comets. 1. Cracks in the oon s crust caused lava to fill large craters, forming, or dark, flat areas. 2. gneous maria rocks are 3 to 4 years old, indicating craters formed after the surface cooled.. Data from suggest that under the oon s crust might lie a solid mantle, then a partly molten mantle and a solid, iron-rich core. F. of oon origin the oon formed 4.6 billion years ago from arth material thrown off when a large object collided with arth. eeting ndividual eeds Copyright Glencoe/cGraw-Hill, a division of the cgraw-hill Companies, nc. ection 3. issions to the oon 1. arly exploration xploring arth s oon a. he first una spacecraft, launched by the in 1959, enabled close study of the oon. b. he anger spacecraft and the unar rbiters of the.. took detailed of the oon in the 1960s. c. Five urveyor.. spacecrafts on the oon. d. stronauts of landed on the oon in 1969. 2. he Clementine spacecraft was placed in lunar orbit in 1994 to the moon s surface. a. Collected data on the content of oon rocks b. apped on the oon s surface c., or craters, are depressions left by objects striking the oon. d. dentified, the largest and deepest impact basin in solar system. he un-arth-oon ystem 33
ame Date Class ote-taking Worksheet (continued) B. apping the oon 1. Data from Clementine yielded a map of the oon showing its. a. he oon s crust is under its impact basins. b. he crust on the side of the oon facing arth is than on the far side. 2. he unar rospector was launched in 1998 to look for clues about the oon s and makeup. a. mall, iron-rich of the oon supports the impact theory of the oon s origin. eeting ndividual eeds b. Findings confirmed that was present in deep craters at poles. Copyright Glencoe/cGraw-Hill, a division of the cgraw-hill Companies, nc. 34 he un-arth-oon ystem