"THE
GREEN PAGES"
EARTH SCIENCE at SPRING VALLEY HIGH SCHOOL
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QUICK LINKS: INDEX 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
UNIT VIII/A: THE EARTH IN SPACE – THE SOLAR SYSTEM
«1. Identify the seasonal changes in the Sun’s noon altitude, positions
of Sunrise/Sunset, and amount of daylight.
a. Most objects in the system are in regular and predictable motion.
b. These motions explain such phenomena as the day, the year, seasons, of the moon, eclipses, and tides.
c. Gravity influences the motions of celestial objects. The force of between two objects in the universe depends on their and the between them. (Question 1)
d. The two principal motions of Earth are:
* - the spinning of Earth about its axis, which produces the daily cycle of daylight and darkness. (Question 1) (Question 2)
* - the movement of Earth in its orbit around the Sun. (Question 1)
e. Several factors act together to cause the seasons (The seasons caused by the distance between the Earth and the Sun!!!):
*Earth revolves around the .
*Earth's axis is tilted degrees (from the perpendicular to the plane of its orbit around the Sun).
* - The axis remains pointed in the same direction (toward the North Star) as Earth journeys around the Sun. The axis is parallel to itself at any position in Earth’s orbit.
f. As a result, Earth's orientation to the Sun continually changes. Sometime the is tilted toward the Sun, and sometimes it is tilted away.
g. The yearly changes in the angle of the Sun and length of daylight brought about by Earth's changing orientation to the Sun cause .
h. Solstice- June 20 or 21. The Earth’s axis is tilted at its most towards the Sun, and marks the longest day and the beginning of summer (in the hemisphere this is the winter solstice). The Sun is directly overhead at the Tropic of (23.5°N) at noon.
i. Solstice- December 21 or 22. The planet's axis is tilted at its most away from the Sun, and marks the shortest day and the beginning of winter (in the southern hemisphere this is the solstice). The Sun is directly overhead at the Tropic of (23.5°S) at noon.
j. (Vernal) Equinox- March 20 or 21. The first day of spring (in the southern hemisphere this is the first day of .) There are 12 hours of and 12 hours of . The Sun is directly overhead at the (0°N) at noon.
k. (Autumnal) Equinox- September 22 or 23. The first day of fall (in the southern hemisphere this is the first day of .) There are hours of daylight and hours of darkness. The Sun is directly overhead at the (0°N) at noon.
l. Seasonal changes can be explained using concepts of density and heat energy. These changes include the shifting of global temperature zones, the shifting of planetary wind and ocean patterns, the occurrence of monsoons, hurricanes, flooding, and severe weather.
(Question 1) (Question 2) (Question 3) (Question 4) (Question 5) (Question 6) (Question 7)
«2. Recognize the path of the Sun during each season at different latitudes.
a. (incoming solar radiation) heats Earth’s surface and atmosphere unequally due to variations in:
*The intensity caused by differences in atmospheric transparency and the angle of , which vary with time of day, latitude, and season.
*Characteristics of the materials absorbing the energy such as color, texture, transparency, state of matter, and specific .
*Duration, which varies with seasons and latitude.
(Question 1) (Question 2) (Question 3) (Question 4) (Question 5) (Question 6)
b. The Sun’s apparent through the sky varies with latitude and season.
c. North of the equator, the Sun always rises in the , travels through the sky, and sets in the . (South of the equator, it rises in the , travels through the sky, and sets in the .)
d. (ALT)- number of degrees above horizon. Straight up is 90°. The horizon is 0°.
e. (AZ)- A way of using degrees to state a compass direction:
*North =
*East =
*South =
*West =f. The path of the Sun at Spring Valley, New York (41°N latitude):
*Summer Solstice- the Sun rises in the (AZ=58°), travels in the sky (ALT=72.5°), and sets in the (AZ=302°).
*Winter Solstice- the Sun rises in the (AZ=121°), travels in the sky (ALT=25.5°), and sets in the (AZ=239°).
*Both Equinoxes- the Sun rises exactly in the (AZ=90°), rises to its average height (ALT=49°), and sets exactly in the (AZ=270°).g. At the Equator: day and night are each always hours long. The Sun always travels in a path (at a 90° angle) to the plane of the horizon. Only on the equinoxes, the Sun rises exactly east and sets exactly west, traveling directly overhead, through the at noon. The noon Sun is never lower than 66.5° altitude.
h. At the Poles: on the equinoxes, the Sun moves along the horizon, never quite or . At the North Pole the Sun "rises" on March 21st and "sets" on September 22. The situation is reversed for the South Pole. During the summer, the Sun never . During the winter, the Sun never . The Sun, when up, always travels in a circle through the sky, to the horizon. The Sun never rises more than 23.5° above the horizon.
i. The Sun can only be directly overhead, at the , at locations between the Tropics of (23.5°N) and (23.5°S). The Sun is at the zenith in New York!
«3. Explain the annual migration of the Sun’s vertical ray as a result of revolution, tilt, and parallelism.
a. The Sun’s rays are vertical when the Sunlight is hitting Earth at a angle.
b. Dates and locations of Sun’s vertical rays:
* solstice – Tropic of Cancer
* equinox - Equator
* solstice – Tropic of Capricorn
* equinox – Equatorc. Throughout the course of one year, the Sun’s vertical rays migrate and between the Tropics of Cancer and Capricorn.
(Question 1) (Question 2) (Question 3) (Question 4) (Question 5) (Question 6) (Question 7)
«4. Compare and contrast the evidences of revolution and rotation.
a. Two pieces of evidence for Earth's Rotation:
*Foucault - Each hour the pendulum shifts approximately 11 degrees in a clockwise direction knocking over all the pins that surround it. The shift is caused by Earth's . If the Earth did not rotate only 2 pins (in a straight line from each other) will be knocked down. At the north pole the apparent rotation would be a full circle of 360° each 24-hour day, or about 15° per hour. The further south you go, the slower the apparent rotation gets, and at the equator there is no rotation at all. Below the equator the apparent rotation begins again, but in the direction.
* Effect- Earth’s rotation causes winds and any other freely moving objects to curve in their paths.
(Question 1) (Question 2) (Question 3) (Question 4) (Question 5) (Question 6) (Question 7)
b. 2 pieces of evidence for Earth's Revolution:
*Parallax Effect- The apparent shift in a 's position that occurs because Earth has moved in its orbit. Parallax refers to the apparent shifting of an object when viewed at different angles. If you view the same object from two different angles, the perspective will change. Hold your thumb out in front of you at arm's length and view it first with your right eye (left eye closed), and then with your left eye (right eye closed). Your thumb appears to move. Astronomers view stars from one side of the Earth's and then from the other side to attempt to detect parallax.
*Seasonal changes in constellations- During the summer, certain constellations are visible in the nighttime sky. During the winter, when the Earth is on the side of the Sun, the nighttime sky faces the opposite side of the , so we see different .
(Question 1) (Question 2) (Question 3) (Question 4) (Question 5)
c. Computing the speed of Earth's rotation (at the equator):
*Circumference of Earth = 40,000 kilometers
*Time for one rotation = 24 hours
*Speed of rotation = Distance/Time = 40,000 km / 24 hr = km/hr (1,038 mi/hr)
d. Computing the speed of Earth's rotation (at the Spring Valley, NY):
*Circumference of Earth at 41°N latitude = 30,289 kilometers
*Time for one rotation = 24 hours
*Speed of rotation = Distance/Time = 30,289 km / 24 hr = km/hr (784 mi/hr)
*Every second, the Earth's rotational motion carries you 351 meters, or about 1,150 feet, through space.
e. Computing the speed of Earth's revolution around the Sun:
*Circumference of Earth's orbit = 940,000,000 kilometers
*Time for one revolution = 365 1/4 days = 8766 hours
*Speed of revolution = Distance/Time = 940,000,000 km / 8766 hr = km/hr = 30 km/sec (66,490 mi/hr)
*Every , the Earth's orbital motion carries you 30 kilometers, or about 18 miles, through space.
«5. Relate Earth’s rate of rotation
to time keeping and longitude.
a. Earth rotates ° every 24 hours.
b. Earth rotates ° per hour. (360°/24hr= °/hr)
c. Earth is divided into time zones, each 15° wide.
d. If you move 15° west, your time by one hour.
e. If you move 15° east, your time by one hour.
f. (GMT)- The time at the Prime Meridian (0° longitude).
g. Chronometer- a very accurate that can keep time in all weather; used in navigation.
h. may be determined by calculating the time difference between the location a person is in and Greenwich Mean Time (GMT). So if the time zone a person is in is three hours ahead of GMT then that person is at 45° longitude (3 hours x 15° per hour = 45°). In order to perform this calculation, however, a person needs to have a set to GMT and needs to determine local time by solar observation or astronomical observation.
i. California is three hours earlier than New York. Its longitude must be west of New York.
j. London, England is five hours later than New York. Its longitude must be east of New York.
k. If you are on a ship, your local time is 2pm, and your chronometer reads 8pm, your longitude must be 90° . [(8-2)x15=90]
l. If you are on a ship, your local time is 11am, and your chronometer reads 9am, you longitude must be 30° . [(11-9)x15=30]
m. - imaginary line on the Earth's surface, generally following the 180° meridian of longitude, where, by international agreement, travelers change dates. Traveling eastward across the line, one subtracts one calendar day; traveling , one adds a day.
SECTION
5 SLIDES (Question
1) (Question 2) (Question
3) (Question 4) (Question
5) (Question 6) (Question
7) (Question 8) (Question
9) (Question 10)
«6.
Locate zenith, horizon, and compass directions on a celestial sphere
model.
a. - the point on the celestial sphere directly above the observer.
b. - where the sky meets the Earth in the distance.
c. Looking at a map with north at the top, is down, is right, and is left.
«7.
Locate Polaris using the Big Dipper.
a. , or the North Star, is located at the end of the handle of the .
b. To find Polaris, use the Dipper. The two stars on the side of the cup opposite the handle are called the “pointer stars.” Draw an arrow from the bottom star through the top star, and it will point to .
«8.
Use the angle of Polaris to determine the observer’s latitude at
different locations.
a. The of Polaris = latitude.
b. An astrolabe (sextant) is an ancient scientific instrument that the Greeks used in the second century B.C. to determine the at which they were located.
c. The astrolabe, which allows the user to measure vertical angles, was very important to sailors in ancient times.
d. Determining the angle between your position on Earth and Polaris determines your .
e. A person standing at the North Pole will find Polaris straight overhead ( °), which is her latitude.
f. A person standing at the equator will find Polaris at the horizon ( °), also her latitude. Polaris is not visible below the .
g. To build an astrolabe:
You need these materials:
Protractor
Tape
Straw
12" of string
A weight (such as a washer, nut, or paper clip)
Directions:
Turn your protractor upside down so the rounded part is facing the ground
Tape the string on the center of the straight edge.
Tie the weight on the end of the string.
Tape the straw on the straight edge of the protractor.
h. To use your astrolabe, look at an object (Polaris) through the , the sight, letting the string hang down the front of the protractor. When the object is in the center of the sight, hold the string tightly against the protractor. While you are still holding the string against the protractor look at the measure of the angle. This angle is your !
«9. Explain how Polaris is used as a navigational tool.
a. Traveling north, Polaris in the sky.
b. Traveling south, Polaris in the sky.
c. Traveling east or west, the altitude of Polaris .
SECTION 9 SLIDES (Question 1) (Question 2) (Question 3) (Question 4) (Question 5) (Question 6) (Question 7) (Question 8) (Question 9) (Question 10)
«10. Explain how the Moon’s rotation and revolution affects its appearance.
a. Earth is orbited by one and many artificial satellites.
b. When we watch the Moon during the course of a month, it looks like it is changing shape. What we are really seeing is reflected from the moon’s surface as it moves around the Earth.
c. The Sun always shines on of the moon, but we cannot always see the entire half that is lit up. The phases are the parts of the lit half that we can see.
d. It takes about one (moonth) for the Moon to complete one cycle of phases.
e. The shape varies from a Moon (when the Earth is between the Sun and the moon) to a Moon (when the Moon is between the Sun and the Earth).
f. The of the Moon in order: new, waxing crescent, first quarter, waxing gibbous, , waning gibbous, last (third) quarter, waning crescent, new, etc.
g. = getting brighter
h. = getting darker
i. = banana shape
j. = more than half lit, less than full.
k. When the R side is lit, it is getting R .
l. When the L side is lit, it is in its L phases.
m. Looking at the shapes of the phases in order, can you see the word, “DOC”?
D = quarter
O = moon
C = crescent
n. At the time of the new moon, the Moon rises at about the same time the rises, and it sets at about the same time the sets. As the days go by (as it waxes to become a crescent moon, a half moon, and a gibbous moon, on the way to a full moon), the Moon rises during the daytime (after the rises), rising later each day, and it sets at nighttime, setting later and later each night.
o. At the full moon, the times of moonrise and moonset have advanced so that the Moon rises about the same time the Sun , and the Moon sets at about the same time the Sun . As the Moon wanes (becoming a half Moon and a crescent moon, on the way to a new moon), the Moon rises during the night, after sunset, rising later each night. It then sets in the daytime, after the Sun rises. Eventually, the Moon rises so late at night that it's actually rising around sunrise, and it's setting around sunset. That's when it's a Moon once again.
SECTION 10 SLIDES (Question 1) (Question 2) (Question 3) (Question 4) (Question 5) (Question 6) (Question 7) (Question 8) (Question 9) (Question 10) (Question 11) (Question 12) (Question 13) (Question 14) (Question 15) (Question 16)
«11. Explain why eclipses are rare events.
a. During a new moon, when the Moon is between the and the , the Moon usually doesn’t block the Sun.
b. During a full moon, when the Earth is between the Sun and the moon, the Earth’s usually doesn’t fall on the moon.
c. The Moon's orbit is tipped by 5 degrees with respect to the Earth's orbit. Therefore, do not occur every month.
d. The three objects ( , , ) are rarely lined up perfectly.
«12. Compare and contrast solar and lunar eclipses.
a. , be they solar or lunar, occur when the Earth, Sun and Moon are in a line.
b. If the Moon is in between the Earth and the Sun, it blocks the view of the Sun from some parts of the Earth, and this produces a eclipse.
c. If the Earth is in between the Sun and Moon, then the Earth will block the light from the Sun before it can get to the Moon. Since moonlight is just the light the Moon reflects from the Sun, this will darken the Moon, and we get a eclipse.
d. Whether it is the Moon between the Earth and Sun, or the other way around, the phenomenon is basically the same: the body in the casts a cone of shadow, and if the outer body happens to move into this cone, we have an .
e. It is important to notice that the shadow is more complicated than just a cone: it actually consists of a darker cone, or umbra, where no reaches, and a lighter region, the penumbra, where only some of the Sunlight is blocked. Whether you will be able to observe a or partial eclipse will depend on which of the two regions you are located in.
SECTION 11 & 12 SLIDES (Question 1) (Question 2) (Question 3) (Question 4) (Question 5) (Question 6) (Question 7) (Question 8) (Question 9) (Question 10) (Question 11)
«13. Describe how the Moon and the Sun cause the tides.
a. - The rise and fall of the surface of oceans, seas, bays, rivers, and other water bodies caused by the gravitational attraction of the Moon and Sun occurring unequally on different parts of the Earth.
b. Approximately 70 percent of Earth’s surface is covered by a relatively thin layer of , which responds to the gravitational attraction of the moon and the Sun with a daily cycle of high and low .
c. The ’s gravity pulls on the Earth, and pulls the water towards it. The water moves up into a slight bulge on the side of the Earth that faces the .
d. At the same time, there is a force pulling water out in the direction of the moon. To understand this force, you need to picture the Earth and the Moon as one unit. Picture two unequal balls on the ends of a stick. If you spin this stick around, you can imagine the force that a particle might feel if it were on the far end of either the Moon or the Earth. It would feel a force outward, away from the center of the spin. This is called the centrifugal force. The water on the far end of the Earth, away from the , is always being pulled out from the center of the spinning Earth-moon unit, like a person being whirled around on a carnival ride.
e. In one (one day), a point on Earth travels from an area of tide (where there is a force pulling water outward), through an area of tide, through an area of tide again (the opposite pull), and through another area of tide, before it returns to the point of origin at high tide. This results in high tides and low tides in a day (called semidiurnal tides).
f. The tides are caused mainly by the gravitational attraction of the and the , but there is also a gravitational attraction between the Earth and the Sun. The effect of the Sun upon the tides is not as significant as the moon’s effects. Basically, the Sun’s pull can heighten the moon’s effects or counteract them, depending on where the Moon is in relation to the Sun.
g. tides- especially high high tides and low low tides that occur during and moons, when the Sun and the Moon are lined up with the Earth.
h. tides- especially low high tides and high low tides that occur during quarter moons, when the gravitational forces of the and the are perpendicular to one another with respect to the Earth.
SECTION 13 SLIDES (Question 1) (Question 2) (Question 3) (Question 4) (Question 5) (Question 6) (Question 7) (Question 8) (Question 9) (Question 10)
«14. Understand the size, scale, and arrangement of the members of the Solar
System (ESRT p.15).
a. The Solar System consists of the (our star), the nine , more than 130 (moons) of the planets, and a large number of small bodies (the comets and asteroids). (There are probably also many more planetary satellites that have not yet been .)
b. The inner Solar System contains the Sun, Mercury, , Earth and .
c. The belt lies between the orbits of Mars and Jupiter, separating the inner planets from the outer planets.
d. The planets of the outer Solar System are Jupiter, , Uranus, and Pluto.
e. The Solar System is mostly empty . The planets are very small compared to the space between them.
f. The contains 99.85% of all the matter in the Solar System.
g. The contain only 0.135% of the mass of the Solar System.
h. contains more than twice the matter of all the other planets combined.
i. of the planets, comets, asteroids, meteoroids, and the interplanetary medium constitute the remaining 0.015%.
j. If the Sun had an equatorial diameter of 25cm (ESRT p.1 and 15), the planets would be this big:25 cm / 1,392,000 km = ? cm / (actual planet diameter) km ***CROSS MULTIPLY!
Mercury - mm
Venus - mm
Earth - mm
Mars - mm
Jupiter - mm ( cm)
Saturn - mm ( cm)
Uranus - mm
Neptune - mm
Pluto - mm
k. If the distance from the Sun to Pluto is 25cm, the distance from the planets to the Sun would be:
25 cm / 5,900,000,000 km = ? cm / (actual planet distance) km ***CROSS MULTIPLY!Mercury - mm ( cm)
Venus - mm ( cm)
Earth - mm ( cm)
Mars - mm ( cm)
Jupiter - mm ( cm)
Saturn - mm ( cm)
Uranus - mm ( cm)
Neptune - mm ( cm)
Pluto - 250mm (25cm)
SECTION 14 SLIDES (Question 1) (Question 2) (Question 3) (Question 4) (Question 5) (Question 6) (Question 7) (Question 8) (Question 9) (Question 10) (Question 11) (Question 12) (Question 13) (Question 14) (Question 15) (Question 16) (Question 17) (Question 18) (Question 19) (Question 20) (Question 21) (Question 22)
«15. Compare/contrast the geocentric and heliocentric models.
a. model- model of the universe with the Earth at the center and all other objects moving around it.
b. model- model of the universe with the Sun at the center and all other objects moving around it.
c. The following is a summary of major achievements in astronomy.
*Among the first people known to have kept astronomical records were the Akkadians who lived some 4,500 years ago in northern Babylonia. The Babylonians accumulated records of astronomical observations for many centuries. The records enabled them to see repeated in the motions of the celestial objects. They used the patterns to predict the positions of the Moon and planets.
*The first record of an of the Sun was made in China (2136 B.C.). The first calendars were made in China (1300 B.C.). The Chinese recorded sightings of many , including Halley’s comet (466 B.C.)
*The Mayans built many monuments and buildings, which were aligned to the position of and Sunset at the equinoxes and . Their calendars kept track of the Sun, Moon and Venus, as well as solar and lunar (1000-2000 years ago).
*Early Greeks held the ("Earth-centered") view of the universe, believing that Earth was a sphere that stayed motionless at the center of the . Orbiting Earth were the seven wanderers (planetai in Greek), which included the Moon, Sun, and the known planets—Mercury, Venus, Mars, Jupiter, and Saturn. To the early Greeks, the stars traveled daily around Earth on a transparent, hollow sphere called the .
*In A.D. 141, Claudius Ptolemy presented the geocentric outlook of the Greeks in its most complicated form in a model that became known as the Ptolemaic system. The Ptolemaic model had the planets moving in circular orbits around a motionless . To explain the motion of planets (the apparent westward, or opposite motion planets exhibit for a period of time as Earth overtakes and passes them) Ptolemy proposed that the planets orbited in small circles (epicycles), revolving along large circles (deferents).
*In the fifth century B.C., the Greek Anaxagoras reasoned that the shines by reflected Sunlight, and because it is a sphere, only half is illuminated at one time. Aristotle (384-322 B.C.) concluded that Earth is spherical.
*The first Greek to acknowledge a Sun-centered, or , universe was Aristarchus (312-230 B.C.). The first successful attempt to establish the size of Earth is credited to Eratosthenes (276-194 B.C.). The greatest of the early Greek astronomers was Hipparchus (second century B.C.), best known for his star catalog.
*Modern astronomy evolved through the work of many dedicated individuals during the 1500s and 1600s. Nicolaus Copernicus (1473-1543) reconstructed the Solar System with the at the center and the orbiting around it, but mistakenly continued to use to represent the orbits of planets.
*Tycho Brahe's (1546-1601) observations were far more precise than any made previously.
*Johannes Kepler (1571-1630) ushered in the new astronomy with his three of planetary motion.
*After constructing his own , Galileo Galilei (1564-1642) made many important discoveries that supported the Copernican view of a Sun-centered Solar System.
*Sir Isaac Newton (1643-1727) was the first to formulate and test the law of universal gravitation, develop the laws of motion, and prove that the force of , combined with the tendency of an object to move in a line (inertia), results in the elliptical orbits discovered by Kepler.
(Question 1) (Question 2) (Question 3) (Question 4)
«16. Compare/contrast terrestrial and Jovian planets.
a. The planets are the four innermost planets in the Solar System, Mercury, Venus, Earth and Mars. They are called terrestrial because they have a compact, surface like the Earth's. The planets, Venus, Earth, and Mars have significant while Mercury has almost none.
b. Jupiter, Saturn, Uranus, and Neptune are known as the (Jupiter-like) planets, because they are all gigantic compared with Earth, and they have a gaseous nature like Jupiter's. The Jovian planets are also referred to as the giants, although some or all of them might have small solid .
c. is a small, dense planet that has no atmosphere and exhibits the greatest extremes of any planet. Its surface is covered by , like our Moon.
d. , the brightest planet in the sky, has a thick, heavy atmosphere composed of 97 percent dioxide, a surface of relatively subdued plains and inactive volcanic features, a surface atmospheric pressure ninety times that of Earth's, and surface temperatures of 475°C (900°F) due to a runaway effect.
e. Mars, the " Planet," has a carbon atmosphere only 1 percent as dense as Earth's, extensive dust storms, numerous inactive volcanoes, many large canyons, and several valleys of debatable origin exhibiting drainage patterns similar to stream valleys on Earth. Mars is red due to the presence of (rust) on the surface.
f. , the largest planet, rotates rapidly, has a banded appearance caused by huge convection currents driven by the planet's interior heat, a Great Red Spot (bigger than ) that varies in size, a thin ring system, and at least sixteen moons (one of the moons, Io, is a volcanically active body).
g. is best known for its system of rings. It also has a dynamic atmosphere with winds up to 930 miles per hour and "storms" similar to Jupiter's Great Red Spot.
h. and are often called "the twins" because of similar structure and composition. A unique feature of Uranus is the fact that it rotates "on its ." Neptune has thin, white, wispy clouds above its main cloud deck and an Earth-sized Great Dark Spot, assumed to be a large rotating storm similar to Jupiter's Great Red Spot.
i. , a small frozen world with one Moon (Charon), may have once been a satellite of Neptune. Pluto's noticeably elongated orbit causes it to occasionally travel inside the orbit of , but with no chance of collision.
(Question 1) (Question 2) (Question 3) (Question 4) (Question 5) (Question 6)
«17. Explain Newton’s Law of
Gravitation with respect to mass and distance.
a. The more mass an object has, the more it has.
b. All objects are attracted to each other by .
c. The closer two objects are to each other, the the gravitational attraction between them.
«18.
Explain how distance from the Sun affects a planet’s orbital velocity
(Kepler’s Laws).
a. The closer a planet is to the Sun, the it moves.
b. is the fastest planet.
c. is the slowest planet.
d. The orbits of all planets are NOT perfect . When a planet is closest to the Sun, it moves .
e. Earth moves fastest during the , when it is closest to the Sun.
f. A line connecting a planet to the Sun will sweep out equal in equal times.
(Question 1) (Question 2) (Question 3) (Question 4) (Question 5) (Question 6) (Question 7) (Question 8) (Question 9) (Question 10) (Question 11) (Question 12) (Question 13) (Question 14) (Question 15) (Question 16) (Question 17)
«19.
Diagram elliptical orbits and analyze their eccentricities (Kepler’s
Laws).
a. The orbits of all planets are , with the Sun at one .
b. - A closed curve resembling a flattened circle (oval).
c. - one of two special points along the major (long) axis of an ellipse. A focus is not at the center of an ellipse unless the ellipse is perfectly circular. Plural = (“foe-sigh”).
d. Eccentricity- Eccentricity is a measure of how circular an is.
e. For a perfectly circular orbit the eccentricity is ; elliptical orbits have eccentricities between zero and . The the eccentricity, the more "squashed" the orbit is. A line segment has an eccentricity of .
f. Eccentricity of an ellipse (ESRT p.1) = the between the foci divided by the length of the axis.
g. The sum of the distances from any point on the curve to the two foci is a (always the same).
h. Here’s how to draw a perfect ellipse. You'll need:
*A flat board, made of any material into which pins or nails can easily be pushed
*Two pins or nails
*A loop of thread or string
*A pen or pencil
*Paper
Place a piece of paper on the board, and stick in the two pins (not too close together). Loop the thread around the pins and pull tight with the tip of the pen. Now move the pen around, always keeping the loop of thread tight. As the pen rotates around the two pins it will trace out an .
i. If you move the pins closer together, the ellipse becomes more (eccentricity decreases).
j. If you move the pins farther apart, the ellipse becomes less (eccentricity increases).
k. If you leave the pins in the same place, but use a longer piece of string, the ellipse will become circular (less eccentric).
l. If you leave the pins in the same place, but use shorter string, the ellipse will become circular (more eccentric).
SECTION 19 SLIDES (Question 1) (Question 2) (Question 3) (Question 4) (Question 5) (Question 6) (Question 7) (Question 8) (Question 9) (Question 10) (Question 11) (Question 12) (Question 13) (Question 14) (Question 15) (Question 15 .pdf)
«20. Understand that the apparent size of the Sun changes seasonally due to
the Earth’s elliptical orbit.
a. During the , when Earth is closest to the Sun, the Sun appears in the sky.
b. During the , the Sun appears smallest.
«21.
Describe meteors, their origin, and cratering as an early geologic activity.
a. - a rock in space.
b. - a meteoroid that has entered Earth’s atmosphere.
c. - a meteor that has landed on Earth’s surface.
d. A meteor occurs when a meteoroid enters the Earth's and vaporizes, heating itself and atmospheric gases so that they glow. Most meteoroids are no more than 1 cm in diameter.
e. High meteor rates occur during meteor , when the Earth runs into a swarm of meteoroids. Showers take place on or close to the same date each year, when the Earth crosses the common orbit of the meteoroids.
f. The number of recovered meteorites has risen dramatically with the discovery that Antarctic ice fields collect and preserve meteorites for millions of .
g. Meteorites are classed as stones, irons, and stony-irons. Stones resemble Earth rocks and are the most meteorites. Carbonaceous chondrites are a type of stony meteorite and may represent unaltered material from early in the history of the Solar . Iron meteorites contain of and nickel and stony-iron meteorites are mixtures of stone and metal.
h. The radioactive elements in meteorites show that most of them solidified at almost the same time as the oldest Moon rocks, about 4.6 billion years ago (the age of the ).
i. The large number of on the Moon and other Solar System objects indicates that they experienced an early period of intense bombardment.
j. Impact craters can be identified in Earth’s crust.
«22.
Describe comets, the eccentricity of their orbits, and the Oort cloud.
a. are chunks of ice and dust. When they come close to the Sun, however, the nucleus is warmed enough by Sunlight to release gas and dust. These flow away from the nucleus to produce the of the comet, which always points away from the .
b. The Sun is surrounded by the Oort cloud, a swarm of beyond the orbit of Pluto. There may be as many as 1 trillion comets in the Oort cloud. Passing stars alter the orbits of Oort cloud comets, causing some of them to enter the planetary system and become visible as new comets. Other comets are thought to come from the Kuiper belt, a disk of just beyond the orbit of Neptune.
c. A comet loses icy material each time it passes the . Eventually, the ice is entirely eroded. The dust particles left behind form meteoroid swarms that produce showers. Some comet nuclei may have rock cores that become asteroids once the surrounding ice is gone.
d. If a large meteoroid or comet struck the , there would be serious local and global consequences. The global consequences might include darkness for weeks or months, very acidic rain, and temporary heating of the atmosphere.
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«23.
Describe the location of the asteroids and their past influence on the
Earth.
a. Most of the known orbit in a belt located between the orbits of and . These asteroids are very widely spread out.
b. Many asteroids are not found in the asteroid belt. The Trojan asteroids, for example, either follow or go before Jupiter in its orbit around the . In addition, the asteroids Hidalgo and Chiron have orbits larger than Jupiter's.
c. Many asteroids have orbits that carry them inside the orbit of the . Within tens of millions of years, these asteroids are likely to be destroyed by striking the Earth.
d. Many asteroids are fragments of asteroids that were shattered by impacts. Most of the small asteroids are the eroded cores of much bodies.
e. An excess of the element iridium, discovered in rocks formed at the end of the Cretaceous period 65 million years ago, suggests that an struck the Earth at that time. The consequences of the impact may have played a role in the Cretaceous extinctions.
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«24.
Describe other planetary satellites/rings
a. Our Moon's surface is covered with from impacts with meteoroids.
b. The period of the Moon is the same as the period of its about the Earth. This arrangement keeps the same face of the Moon turned toward the Earth.
c. Phobos and Deimos, the satellites of , are believed to be captured asteroids.
d. The intense tidal heating of Jupiter’s moon, Io, makes it the most volcanically active body in the System. Volcanic material is deposited so rapidly on Io's surface that all evidence of impact cratering has been covered up.
e. Jupiter’s moon, Europa, has a very smooth, icy surface even though it is made mostly of rock. Europa's surface has been smoothed by glacier-like flows and, probably, by flows of water from the interior. A thick of water probably exists below its icy crust.
f. Saturn's largest satellite is Titan. Its atmosphere contains mostly nitrogen and is thicker than the Earth's. Titan is cold enough that atmospheric ethane can to liquid form. In fact, Titan may have ethane rain and lakes or oceans of ethane.
g. Triton orbits Neptune in a retrograde direction and is slowly spiraling inward. Triton probably formed elsewhere and was captured into a orbit.
h. The of Jupiter, Saturn, Uranus and Neptune are very thin and consist of many individually orbiting particles (rock and ice).
i. The 32 Largest Objects in Solar System:
