Download 11-4-10 Aim: What are the apparent motions of the stars and planets?

11-4-10
Aim: What are the apparent
motions of the stars and planets?
Do Now:
1. If there was another planet (Z) that was in
between Mercury and Venus, estimate its distance
from the sun, diameter, period of revolution. Also
tell me if it would be terrestrial or jovian?
2. List the planets in order of increasing eccentricity
of their orbits.
3. HW: R&H pp. 60-62, A&E #1-14
Celestial Sphere- an imaginary dome
showing the portion of the sky visible
from your location.
Parts of the Celestial Sphere
Meridian
• Zenith – point
directly overhead.
• Meridian – line
connecting north
to south passing
through your
zenith.
• Horizon – where
the ground meets
the sky 360 deg.
around you.
Daily Motion of Stars and Planets
• Because the earth
rotates 15deg/hr
from west to east
all celestial
objects will
appear to rise in
the east and set
in the west. This
includes all stars,
including the sun,
the moon and the
planets.
Retrograde Motion- the apparent
backward motion of the planets as the
earth passes them in their orbit
Earth’s elliptical orbit about the sun
11-5-10
Aim: What causes the seasons?
• Do Now:
• 1. Draw a celestial sphere for New York. Be
sure to label meridian, zenith, horizon,
compass directions and the location of Polaris.
• 2. What is a direct ray?
• 3. What is aphelion and perihelion?
www.brainpop.com/science#885B39
• Google “Randy Russell portfolio on seasons”
www.msu.edu/.webloc
11-8-10
Aim: What are the models that help
explain celestial motion?
• Do Now:
• 1. I see the sun directly overhead at noon on
June 21, where am I and what compass direction
did I look to see the sunrise?
• 2. As altitude of the sun increases, intenstiy___.
• 3. Explain retrograde motion.
• HW R&H pp.63-64, A&E #15-19, Finish Lab.
11-9-10
How is the earth moving?
• Do Now: QUIZ
• For each lettered position on the board,
indicate the date, location of the direct rays,
name of the day and the # of daylight hours at
the North Pole, N.Y., Equator, and the South
Pole.
•
• HW: R&H pp.65-70, A&E #20-40
Evidence of the earth’s rotation
• 1. Night and day- as the earth rotates 15 deg./hour from
west to east all locations will experience light and dark in
24 hours.
• 2. Apparent rising and setting of all celestial objects.
• 3. Motions of the Foucault Pendulum- a freely swinging
pendulum appears to change direction as a result of the
earth’s rotation.
• 4. The Coriolis Effect- winds and water will be deflected to
the right in the northern hemisphere and to the left in the
southern hemisphere as result of earth’s rotation.
• 5. Star Trails- time lapse photos taken of stars seem to
make circular trails around Polaris.
Foucault Pendulum
Coriolis Effect
Evidence of Earth’s Revolution
• Different constellations visible at different times of the
year
• Ecliptic- the apparent path that the sun makes through
the stars as a result of the earth’s revolution. (p.67)
11-10-10
Aim: What causes the phases of the moon?
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•
•
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Do Now:
Name the thing responsible for each:
A. Night/day
B. Retrograde motion
C. Different constellations visible at different times of year.
D. Star Trails
E. Motions of Foucault Pendulum
F. Ecliptic
G. Seasons
H. Apparent path of the sun during the day.
• HW- R&H pp. 71-74, A&E # 41-57
Moon’s Revolution and Phases of the
Moon
Moon Facts
Rotation = 27.3 days
Revolution = 27.3 days (Seiderial Month)
*because the moon rotates and revolves at the same
speed we always see the same side of the moon.
Full Cycle of Phases = 29.5 days (Sonadal Month)
Reason- because the earth revolves around the sun at the
same time the moon revolves around the earth, it
takes 2 extra days for the moon to catch up to earth in
its orbit. The moon’s revolution around the earth is
what causes us to see different phases of the moon.
Orbit = counterclockwise in an ellipse and on a 5 degree
tilt.
11-12-10
Aim: What causes tides?
• Do Now:
• 1. What is the difference between a siderial
and a sonadal month?
• 2. Because the moon rotates and revolves at
the same speed, what does this cause to
happen?
• HW: p.76 #1-29 A&E, Finish Lab.
Spring Tides and Neap Tidescontrolled by the gravitational pull of
the moon but enhanced by the
gravitaional pull of the sun.
Tides Animation
• Spring Tide – when the moon and the sun pull
in the same direction creating the highest high
tides and the lowest low tides for the month.
• Neap Tide – when the sun and the moon are
at right angles to the earth, high tide stays
with the moon creating the lowest high and
highest low tides for the month.
www.mmscrusaders.com/.webloc
Eclipses
Caused when the moon’s shadow
blocks out the sun or when the earth’s
shadow blocks out the moon.
Solar Eclipse
Lunar Eclipse
The reason we do not experience eclipses every month is
because the moon’s orbit is on a 5 deg. Tilt causing the
earth, sun and moon not to lign up perfectly.
What a lunar eclipse looks like