Page 450 - 9780077418427.pdf

/Users/user-f465/Desktop
tiL12214_ch16_405-432.indd Page 427 9/3/10 6:19 PM user-f465
tiL12214_ch16_405-432.indd Page 427 9/3/10 6:19 PM user-f465 /Users/user-f465/Desktop

location is called the apparent local noon. The time at a given place that equinoxes (p. 409)
is determined by a sundial is called the apparent local solar time. It is first quarter (p. 423)
the basis for an averaged, uniform standard time called the mean solar full moon (p. 423)
time. Mean solar time is the time used to set clocks. international date line (p. 416)
A sidereal day is the interval between two consecutive crossings last quarter (p. 423)
of the celestial meridian by a star. An apparent solar day is the interval latitude (p. 412)
between two consecutive crossings of the celestial meridian by the Sun, longitude (p. 412)
from one apparent solar noon to the next. A mean solar day is 24 hours lunar eclipse (p. 424)
as determined from mean solar time. The equation of time shows how lunar highlands (p. 419)
the local solar time is faster or slower than the clock time during dif- maria (p. 419)
ferent days of the year. mean solar day (p. 414)
Earth’s surface is divided into one-hour standard time zones that mean solar time (p. 414)
are about 15° of meridian wide. The international date line is the 180° meridians (p. 412)
meridian; you gain a day if you cross this line while traveling westward neap tide (p. 426)
and repeat a day if you are traveling eastward. new moon (p. 423)
A tropical year is the interval between two consecutive spring noon (p. 413)
equinoxes. A sidereal year is the interval of time between two consecu- parallels (p. 412)
tive crossings of a star by the Sun. It is the tropical year that is used penumbra (p. 423)
as a standard time interval for the calendar year. A sidereal month is perigee (p. 426)
the interval of time between two consecutive crossings of a star by the plane of the ecliptic (p. 406)
Moon. The synodic month is the interval of time from a new moon to precession (p. 411)
the next new moon. The synodic month is about 29½ days long, which prime meridian (p. 412)
is about one-twelfth of a year. revolution (p. 408)
The surface of the Moon has light-colored mountainous regions rotation (p. 408)
called highlands, smooth dark areas called maria, and many sizes of craters, sidereal day (p. 414)
and it is covered by a layer of fine dust. Samples of rocks returned to Earth sidereal month (p. 419)
by Apollo astronauts revealed that the highlands are composed of basalt sidereal year (p. 418)
breccias that were formed some 4 billion years ago. The maria are basalts solstices (p. 409)
that formed from solidified lava some 3.1 to 3.8 billion years ago. This and spring equinox (p. 409)
other data indicate that the Moon developed through four stages. spring tides (p. 426)
Earth and the Moon act as a system, with both bodies revolving standard time zones (p. 416)
around a common center of mass located under Earth’s surface. This summer solstice (p. 409)
combined motion around the Sun produces three phenomena: (1) as synodic month (p. 419)
the Earth-Moon system revolves around the Sun, different parts of the tides (p. 424)
illuminated lunar surface, called phases, are visible from Earth; (2) a total solar eclipse (p. 424)
solar eclipse is observed where the Moon’s shadow falls on Earth, and a tropical year (p. 417)
lunar eclipse is observed where Earth’s shadow falls on the Moon; and tropic of Cancer (p. 413)
(3) the tides, a periodic rising and falling of sea level, are produced by tropic of Capricorn (p. 413)
gravitational attractions of the Moon and Sun and by the movement of umbra (p. 423)
the Earth-Moon system. vernal equinox (p. 409)
winter solstice (p. 409)
KEY TERMS
APPLYING THE CONCEPTS
annular eclipse (p. 424)
Antarctic Circle (p. 413) 1. The plane of Earth’s orbit is called the
apogee (p. 426) a. plane of Earth.
apparent local noon (p. 413) b. plane of the solar system.
apparent local solar time (p. 413) c. plane of the ecliptic.
d. plane of the Sun.
apparent solar day (p. 414)
Arctic Circle (p. 413) 2. The spinning of a planet on its axis, an imaginary line through
its poles, is called
autumnal equinox (p. 409)
a. 24 hour day.
Coriolis effect (p. 411)
b. rotation.
daylight saving time (p. 416)
c. revolution.
eclipse (p. 423)
d. retrograde motion.
equation of time (p. 415)

16-23 CHAPTER 16 Earth in Space 427