1. The Solar System : Planets
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2. SOLAR SYSTEM The Sun 8 Planets 3+ Dwarf Planets Over 150 moons /
satellites of the planets
Comets, meteors, asteroids,
and interplanetary dust/space
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3. Simplified Evolution of Solar System
In the beginning, our Solar System was a huge disc of dirt, rocks, gas, ice, etc.
In the middle of this disc, the Sun formed itself and began to glow.
In some distances from the centre, the planets emerged from these rings of dirt, rocks and gas.

4. Scale of Solar System : Distances
Spacing between adjacent planets roughly doubles. Most orbits are roughly circular.
Distance from Sun to Pluto: 40AU or about 1/1000 of a light year.
All orbit in same direction. Most in same plane.

5. Scale of Solar System : Sizes

6. SUN : The Star Composition: 75% hydrogen and 25% helium by mass
Age: The Sun’s age is about 5 billion years.
Differential rotation duration
At the equator the surface rotates once every 25.4 days
while near the poles it rotates once every 36 days
Core conditions
Temperature is 15.6 million Kelvin
Pressure is 250 billion atmospheres
Differential rotation dependent on its gaseous nature
Equator speed much higher than polar speed
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7. Sun’s energy comes from nuclear fusion (in which hydrogen
is converted to helium within sun’s core).
This energy is released as heat and light.
Our sun is classified as a yellow main sequence star.
A star’s temperature determines its “color.” The coldest stars are red. The hottest stars are blue.
Surface temperature (Corona) : K
In nuclear fusion, a little bit of mass gets converted into energy
E=m c^2
Red Giants: Betelgeuse, Antares, Aldebaran, etc
Blue Giants: Rigel, Vega, Deneb, etc
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8. Geocentric vs. Heliocentric Theory
Geocentric Theory (or “Ptolemaic” Theory – pronounced “Tole-ah-may-ic”) is an ancient view of the universe based primarily on religion, philosophy, and mathematical ideals.
Heliocentric Theory (or “Copernican” Theory) is a revised view of the universe based on the studies of Nicholas Copernicus, who was a mathematician in the 1500’s.
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10. PLANETS
A planet is a large, round heavenly body that orbits a star and shines with light reflected from the star.
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11. The Planets of the Solar System
Planets are categorized according to composition and size. There are two main categories of planets:
Small rocky planets (Mercury, Venus, Earth, Mars, and Pluto)
Gas giants (Jupiter, Saturn, Uranus, and Neptune)
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12. PLANETS: Revised Definition
In the Solar System, a planet is a celestial body that:
is in orbit around the Sun,
has sufficient mass to assume
hydrostatic equilibrium (a nearly
round shape), and
has "cleared the neighbourhood"
around its orbit.
A non-satellite body fulfilling only the first two of these criteria is classified as a "dwarf planet". 
The definition of "planet" set in 2006 by the International Astronomical Union (IAU).
Pluto is 1/20th the size of Mercury and 10 times larger than Ceres.
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13. Revised Planets of the Solar System
Small rocky planets (Mercury, Venus, Earth, and Mars)
Gas giants (Jupiter, Saturn, Uranus, and Neptune)
5 Dwarf Planets
Ceres, Pluto, Haumea, Makemake, and Eris.
Quaoar is a newly discovered Kuiper Belt object, found in June 2002 by Chad Trujillo and Mike Brown at Caltech in Pasadena. It's the largest Kuiper Belt object currently known, half the diameter of Pluto (about 1/8 the volume), and 1.6 billion kilometers (1 billion miles) further away than Pluto.
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14. The Relative Size of the Planets in the Solar System
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15. What are the nine planets?
HINT: My Very Educated Mother Just Showed Us Nine Planets
My Very Educated Mother Just Served Us Nachos
Mercury
Venus
Earth
Mars
Jupiter
Saturn
Uranus
Neptune
Pluto
My Very Educated Mother Just Sent Us Nine Pizzas
Mother Very Easily Made a Jam Sandwich Using Nectarines
^ ASTROID BELT
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16. MERCURY Closest planet to the sun About the size of Earth’s moon
Takes 88 days to complete one revolution around the sun
No atmosphere
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17. MERCURY Orbit Appears to travel fastest 8th largest in size
highly eccentric (oval)
perihelion (closest point) is 46 million km
aphelion (farthest point) is 70 million km
Appears to travel fastest
8th largest in size
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18. VENUS 2nd planet from Sun 6th largest in size
Brightest object in the early morning/evening sky
Also called “morning star” and “evening star”
Very dry atmosphere
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19. VENUS Greenhouse Effect: Inferior/Inner planet
Carbon dioxide in the atmosphere traps heat causing the surface temperature to increase upto F.
Inferior/Inner planet
Shows phases when viewed from Earth
Galileo observed phases
Copernicus used data to develop heliocentric theory.
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20. EARTH: The Blue Planet 3rd planet from the Sun
period of rotation: 24 hours
period of revolution: days
It is called the blue planet because of water
Earth’s surface is composed of 71% water
Oceans help maintain Earth’s stable temperatures.
Only planet with known life
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21. Earth has a distinct atmosphere.
It screens Earth’s surface from harmful radiation from the sun.
It prevents meteorites from reaching Earth’s surface.
It traps heat to help maintain Earth’s stable temperatures.
Scattering of light by the atmosphere makes the sky look blue in the day time and red at sunset/sunrise.
Otherwise, sky would have looked dark even in day time.
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22. EARTH’s Moon Earth has one moon, about 1/6 mass of earth.
It takes the same amount of time for the moon to rotate once on its axis as it does for it to orbit the earth (27.3 days).
Thus, the same side of the moon always faces us.
The moon’s surface is covered in dust and rocky debris from meteor impacts.
It has no water or atmosphere.
The dark areas of the moon are large craters called maria (Latin: “seas”).
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23. The moon reflects light from the sun onto the earth’s surface
The moon reflects light from the sun onto the earth’s surface. Sometimes the moon may appear reddish-brown in color as the sunlight is deflected through dust in the earth’s atmosphere.
The moon’s gravitational effects on the earth are most apparent in the “coming” and “going” of the tides .
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24. EARTH Age: At least 4 1/2 billion years
Mass: 6,600,000,000,000,000,000,000 (6.6 sextillion) tons (6.0 sextillion metric tons).
Surface features: Highest land—Mount Everest, 29,035 feet (8,850 meters) above sea level. Lowest land—shore of Dead Sea, about 1,310 feet (399 meters) below sea.
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25. Temperature: Highest, 136 °F (58 °C) at Al Aziziyah, Libya
Temperature: Highest, 136 °F (58 °C) at Al Aziziyah, Libya. Lowest, °F (-89.6 °C) at Vostok Station in Antarctica. Average surface temperature, 59 °F (15 °C).
Chemical makeup of the earth's crust (in percent of the crust's weight): oxygen 46.6, silicon 27.7, aluminum 8.1, iron 5.0, calcium 3.6, sodium 2.8, potassium 2.6, magnesium 2.0, and other elements totaling 1.6.
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26. Temperature: Highest, 134 °F (56
Temperature: Highest, 134 °F (56.7 °C) at Greenland Ranch in Death Valley, CA on July 10, Lowest, °F (-89.6 °C) at Vostok Station in Antarctica. Average surface temperature, 59 °F (15 °C).
Chemical makeup of the earth's crust (in percent of the crust's weight): oxygen 46.6, silicon 27.7, aluminum 8.1, iron 5.0, calcium 3.6, sodium 2.8, potassium 2.6, magnesium 2.0, and other elements totaling 1.6.
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27. Size Comparison: Radius
Radius of Sun ~ 440,000 miles
Radius of Earth ~ 4000 miles
Radius of Moon ~ 1080 miles
Radius of Sun is 110 times the radius of Earth (10 times the radius of Jupiter), and radius of Earth is 4 times the radius of Moon.
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28. MARS: The Red planet Mars is the 4th Planet from the Sun
Solid carbon dioxide is found at the poles
Mars is known as the Red Planet because its soil is red colored
Mons Olympus –
largest volcano
Moons:
Phobos and Deimos
Phobos (FEAR) and Deimos (DREAD/PANIC)
They are quite small (<15km) and look rather like potatoes than like moons.
Mars has been visited by robotic vehicles: Pathfinder, Spirit and Opportunity
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29. Asteroid Belt : Between Mars and Jupiter
Roughly 2 million rocks between Mars and Jupiter.
Largest object, Ceres, is about 1000km across, but most objects are much, much smaller.
Typically smaller than comets and larger than meteoroids.
Largest are spherical (gravity dominates) but smaller can be irregularly shaped.
175 million miles broad annulus
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30. JUPITER 5th planet from the sun Largest planet in the solar system
Jupiter contains over 70% of the mass in the solar system outside the Sun.
It is about 11 times the radius and 330 times the mass of the earth.
One-tenth the radius of the sun
From the earth, there are two obvious clues to this:
1. Jupiter, which rotates extremely rapidly (a period of about 10 hours), has a significant bulge at the equator. We call this oblateness, and
Jupiter has an oblateness of about 6%, which means that the equatorial diameter is 6% greater than the polar diameter.
2. In addition, Jupiter rotates differentially, just as the Sun does. The period of rotation at the poles is about 10 minutes less than that of the equator, while the interior rotates at an intermediate speed.
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31. 2nd brightest planet in the sky
Giant red spot
2nd brightest planet in the sky
It is the first representative of the outer solar system.
Unlike the inner planets, Jupiter is not a solid body, but instead is a ball of gas and liquid (mostly hydrogen and helium).
Galeilian Moons: Io, Europa, Callisto, Ganymede Io
Europa
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32. SATURN Sixth planet from the sun.
Saturn is a gas giant with strong surface winds (500 m/sec).
Saturn is less dense than water.
Saturn’s magnetic field is 20x less than Jupiter's, but its core rotation period (10.5 hours) is similar.
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33. SATURN’s Moons Titan is larger than planet Mercury!
Mimas has a huge crater.
Epimetheus and Janus, just inside the orbit of Mimas, are continually exchanging orbits with one another in a "waltz" -- they are called the co-orbital satellites.
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34. URANUS Seventh planet from the sun
Most distant planet you can see without using a telescope
Has faint rings
I. Uranus (This data is from:
A. Discovery and Orbit
Uranus was discovered in 1781 by Herschel. This caused a sensation, because everyone had assumed they knew all the planets that there were. Its orbit is very slightly elliptical, its year is 84 Earth years long (because -- remember P2=a3 -- it's at an average distance "a" of A.U.). Its weirdest feature is that it's turned on its side: its axial tilt is 97deg to the plane of its orbit around the Sun (the ecliptic). Like the other planets, its own equator dominates the dynamics of its ring-and-moons system (not the plane of its orbit around the Sun), so the moons' orbits are really easy to measure right now, as the planet's south pole is pointing toward the inner solar system.
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35. NEPTUNE Eighth planet from the sun
The blue coloration of Neptune is probably due to the presence of methane
Uranus is unique among the planets in the Solar System because of its axial tilt. While Earth is tilted at a mere 23.5 degrees, Uranus has rolled over completely sideways, with an axial tilt of 99-degrees. This has a significant impact on the planet’s seasons. The north pole of Uranus experiences 42 years of complete darkness, followed by 42 years of sunlight, where the Sun never dips below in the horizon. Astronomers aren’t sure why Uranus is flipped over sideways, but they think an impact from a protoplanet early in its history gave it the momentum it needed to roll over.
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36. Discovery of Uranus and Neptune
Sir William Herschel in England discovered Uranus on March 13, 1781.
Irregularities in the predicted orbit of Uranus led astronomers Urbain Le Verrier in Paris and John Couch Adams in Cambridge to separately begin calculations to determine the nature and position of a new planet. Eventually, Neptune was discovered on September 23, 1846 by Berlin Observatory.
It was a sensational moment for 19th century science and dramatic confirmation of Newton’s gravitational theory.
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37. PLUTO : Dwarf planet
Formerly, ninth planet from the sun
Pluto used to be the farthest and the smallest planet from the sun
Rocky surface surrounded by frozen gases
Pluto was located by 24-year old Clyde Tombaugh and named in 1930.
The name Pluto was proposed by Venetia Burney, a eleven-year-old schoolgirl in Oxford, England, after the name for the god of the underworld.
The name Pluto was proposed by Venetia Burney (1918–2009), an eleven-year-old schoolgirl in Oxford, England.[32] Venetia was interested in classical mythology as well as astronomy, and considered the name, a name for the god of the underworld, appropriate for such a presumably dark and cold world.
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38. Pluto has only one moon, Charon, and was discovered only in 1978.
Charon is half the size of Pluto itself, which is unusually large for a moon.
Because they are so close in size, sometimes Pluto and Charon are considered to be double-planet.
Pluto seems to lie on its side: its equator points straight up, and one of its poles points directly at the sun.
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39. Planets and Greek Mythology
Mercury (Hermes) is the god of commerce, travel and thievery in Roman mythology.
The planet probably received this name because it moves so quickly across the sky.
Venus (Aphrodite) is the Roman goddess of love and beauty.
The planet is aptly named since it makes a beautiful sight in the sky, with only the Sun and the Moon being brighter.
Earth (Gaia) is the only planet whose English name does not derive from Greek/Roman mythology.
The name derives from Old English and Germanic.
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40. Planets and Greek Mythology
Mars (Ares) is the Roman god of War. The planet probably got this name due to its red color.
Jupiter (Zeus) was the King of the Gods in Roman mythology, making the name a good choice for the largest planet in our solar system.
Saturn (Cronus) is the Roman god of agriculture.
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41. Planets and Greek Mythology
Uranus is the ancient Roman deity of the Heavens, the earliest supreme god.
Neptune (Poseidon), was the Roman god of the Sea. Given the beautiful blue color of this planet, the name is an excellent choice!
Pluto (Hades) is the Roman god of the underworld in Roman mythology. Perhaps the planet received this name because it's so far from the Sun that it is in perpetual darkness.
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42. Planet Temperatures
All planets revolve around the sun and are all at different distances from the sun.
The farther the planet is away from the sun, the colder it will be.
Planet
Temp. (C)
Mercury
150
Venus
450
Earth
Mars
-50
Jupiter
-150
Saturn
-190
Uranus
-210
Neptune
-230
Pluto
-250
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43. Planet’s Distance from the Sun
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44. Number of Moons for Each Planet
Each planet has a different number of moons.
Planet
Moons
Mercury, Venus
Earth 1
Mars 2
Jupiter 63
Saturn 61
Uranus 27
Neptune 13
(out of date for number of moons)
Pluto has 3 moons.
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45. Two ways of Discovering Planets of other stars
Observe a slight “wobble” of the star due to gravitational effects of the planet.
Observe variation in the brightness of star due to eclipse as the planet passes between us and the star (or in total light received as star eclipses the planet).

46. Wobble Amplified: Motion of two revolving bodies under mutual gravity
If the mass of the star
is much higher than
the mass of the planet,
then the distance of
the center of the mass
is much closer to the star
than to the planet.
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47. Wobble Amplified: Motion of two revolving bodies under mutual gravity
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48. Telltale Tug of a Planet
Both the planet and the star revolve around the common center of gravity.
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49. Star eclipsing planet, reducing total light
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50. Planet eclipsing star, reducing total light
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51. Examples http://antwrp.gsfc.nasa.gov/apod/ap050510.html
First image of a extra-solar planet. 
The planet was discovered by the gravitational wobble it created on its parent star, Epsilon Eridani. 
CoRoT-7b was discovered by noting a predictable slight decrease in the brightness of its parent star
Combination of wobble and partial eclipse.
Celestia Exploration Activity:
Solar System Exploration:
Welcome to the Planets:
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52. Beyond Planets: Kuiper Belt
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53. Kuiper belt (30-100 AU) contains 100,000 comets Oort cloud extends out
to about 50,000 AU
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54. Solar System Debris : Comets
Comet Halley (1986)‏
Comet Hale-Bopp (1997)‏
Short Period Comets
Long Period Comets
year orbits
Halley’s period : 76 year
Orbits close to ecliptic
Originate in Kuiper Belt
A passing star may redirect Oort cloud objects, creating long period comets.
Kuiper Belt object can be redirected by Neptune, creating a short-period comet.
105 or 106 year orbits
Orbits: random orientations
and large ellipticities
Originate in Oort Cloud

55. Comet Trajectory

56. Perseid Meteor Shower in August
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57. Leonid Meteor Shower: Debris from Comet Tempel Tuttle
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58. Leonid Meteor Shower in November
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59. Why Meteor Shower is best after Midnight ?
Orbital Velocity
Rotational Velocity

60. Two Showers for Halley