Beyond Planet Earth Mr Ahearn Earth Science 2010
Beyond Planet Earth Mr. Ahearn Earth Science 2010
Phases of the Moon • Moon completes one revolution around Earth one month. • Lighted area appears to change shape (phases)
Eclipses • Lunar • Solar
Angular Diameter of Celestial Objects • Angular diameter is the angle formed between the sides of an object and your eye • Depends on objects size and distance away. (closer = larger, further = smaller) • Celestial objects change in size in cyclic manner. • Sun’s angular diameter is slightly bigger in winter than summer b/c it is closer.
Tides • Twice daily rise and fall of oceans. • Bay of Fundy (Canada) greatest difference in high and low tide (49 ft. ) • Caused by gravitational pull of moon and sun on ocean water. • High tide water attracted toward moon, and on opposite side where there is less force pulling water toward earth.
Tides • Spring tide- highest high and lowest low tide (2 x/month) during full and new moon. • Neap tide- smallest difference in tides, 1 st and last ¼ moons
Answer Questions #1 -15 Review Book p. 276
Geometry of Orbits • Planets that move around the sun have orbits that are slightly flattened circles called ellipses. (two foci along a major axis) • Foci close more circular. • Foci near ends of circle long and narrow ellipse
Calculate Eccentricity = distance between foci length of major axis ex. ) distance b/w foci = 4 cm major axis = 5 cm What is the eccentricity?
The Force of Gravity • Gravity is a fore of attractions b/w objects – Depends on mass and distance • Gravity holds planets and other objects in orbit. (satellite) – Satellites move fastest when closest to sun & slowest when farthest – Elliptical path depends on gravity and inertia (tendency to remain @ rest)
The Solar System
Big Bang • Rapid expansion of concentrated matter that created the universe.
Earth is Unique • Only planet with liquid water. • Only planet w/ atmosphere w/ abundant free oxygen. ESRT p. 15
Asteroids, Meteors, and Comets • Asteroids- rocky objects found mostly in the belt b/w Mars and Jupiter. • Meteors- small solid particle from space caught by earth’s gravity, burn as enter earth’s atmosphere. • Comets- Icy object that most likely originated in region beyond the planets
Answer Questions #16 -33 Review book p. 283
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